Merge branch '3.0' of https://github.com/taosdata/TDengine into fix/hzcheng_3.0

docs-examples/.gitignore

+.vscode
+*.lock
+.idea
\ No newline at end of file

docs-examples/.gitignre

+.vscode
+*.lock
\ No newline at end of file

docs-examples/R/connect_native.r

+if (! "RJDBC" %in% installed.packages()[, "Package"]) {
+  install.packages('RJDBC', repos='http://cran.us.r-project.org')
+}
+
+# ANCHOR: demo
+library("DBI")
+library("rJava")
+library("RJDBC")
+
+args<- commandArgs(trailingOnly = TRUE)
+driver_path = args[1] # path to jdbc-driver for example: "/root/taos-jdbcdriver-2.0.37-dist.jar"
+driver = JDBC("com.taosdata.jdbc.TSDBDriver", driver_path)
+conn = dbConnect(driver, "jdbc:TAOS://127.0.0.1:6030/?user=root&password=taosdata")
+dbGetQuery(conn, "SELECT server_version()")
+dbDisconnect(conn)
+# ANCHOR_END: demo
\ No newline at end of file

docs-examples/R/connect_rest.r

+if (! "RJDBC" %in% installed.packages()[, "Package"]) {
+  install.packages('RJDBC', repos='http://cran.us.r-project.org')
+}
+
+library("DBI")
+library("rJava")
+library("RJDBC")
+driver_path = "/home/debug/build/lib/taos-jdbcdriver-2.0.38-dist.jar"
+driver = JDBC("com.taosdata.jdbc.rs.RestfulDriver", driver_path)
+conn = dbConnect(driver, "jdbc:TAOS-RS://localhost:6041?user=root&password=taosdata")
+dbGetQuery(conn, "SELECT server_version()")
+dbDisconnect(conn)
\ No newline at end of file

docs-examples/c/.gitignore

+*
+!*.c
+!.gitignore

docs-examples/c/async_query_example.c

+// compile with:
+// gcc -o async_query_example async_query_example.c -ltaos
+
+#include <inttypes.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/time.h>
+#include <taos.h>
+
+typedef int16_t VarDataLenT;
+
+#define TSDB_NCHAR_SIZE sizeof(int32_t)
+#define VARSTR_HEADER_SIZE sizeof(VarDataLenT)
+
+#define GET_FLOAT_VAL(x) (*(float *)(x))
+#define GET_DOUBLE_VAL(x) (*(double *)(x))
+
+#define varDataLen(v) ((VarDataLenT *)(v))[0]
+
+int printRow(char *str, TAOS_ROW row, TAOS_FIELD *fields, int numFields) {
+  int  len = 0;
+  char split = ' ';
+
+  for (int i = 0; i < numFields; ++i) {
+    if (i > 0) {
+      str[len++] = split;
+    }
+
+    if (row[i] == NULL) {
+      len += sprintf(str + len, "%s", "NULL");
+      continue;
+    }
+
+    switch (fields[i].type) {
+      case TSDB_DATA_TYPE_TINYINT:
+        len += sprintf(str + len, "%d", *((int8_t *)row[i]));
+        break;
+
+      case TSDB_DATA_TYPE_UTINYINT:
+        len += sprintf(str + len, "%u", *((uint8_t *)row[i]));
+        break;
+
+      case TSDB_DATA_TYPE_SMALLINT:
+        len += sprintf(str + len, "%d", *((int16_t *)row[i]));
+        break;
+
+      case TSDB_DATA_TYPE_USMALLINT:
+        len += sprintf(str + len, "%u", *((uint16_t *)row[i]));
+        break;
+
+      case TSDB_DATA_TYPE_INT:
+        len += sprintf(str + len, "%d", *((int32_t *)row[i]));
+        break;
+
+      case TSDB_DATA_TYPE_UINT:
+        len += sprintf(str + len, "%u", *((uint32_t *)row[i]));
+        break;
+
+      case TSDB_DATA_TYPE_BIGINT:
+        len += sprintf(str + len, "%" PRId64, *((int64_t *)row[i]));
+        break;
+
+      case TSDB_DATA_TYPE_UBIGINT:
+        len += sprintf(str + len, "%" PRIu64, *((uint64_t *)row[i]));
+        break;
+
+      case TSDB_DATA_TYPE_FLOAT: {
+        float fv = 0;
+        fv = GET_FLOAT_VAL(row[i]);
+        len += sprintf(str + len, "%f", fv);
+      } break;
+
+      case TSDB_DATA_TYPE_DOUBLE: {
+        double dv = 0;
+        dv = GET_DOUBLE_VAL(row[i]);
+        len += sprintf(str + len, "%lf", dv);
+      } break;
+
+      case TSDB_DATA_TYPE_BINARY:
+      case TSDB_DATA_TYPE_NCHAR: {
+        int32_t charLen = varDataLen((char *)row[i] - VARSTR_HEADER_SIZE);
+        memcpy(str + len, row[i], charLen);
+        len += charLen;
+      } break;
+
+      case TSDB_DATA_TYPE_TIMESTAMP:
+        len += sprintf(str + len, "%" PRId64, *((int64_t *)row[i]));
+        break;
+
+      case TSDB_DATA_TYPE_BOOL:
+        len += sprintf(str + len, "%d", *((int8_t *)row[i]));
+      default:
+        break;
+    }
+  }
+
+  return len;
+}
+
+void printHeader(TAOS_RES *res) {
+  int         numFields = taos_num_fields(res);
+  TAOS_FIELD *fields = taos_fetch_fields(res);
+  char        header[256] = {0};
+  int         len = 0;
+  for (int i = 0; i < numFields; ++i) {
+    len += sprintf(header + len, "%s ", fields[i].name);
+  }
+  puts(header);
+}
+
+// ANCHOR: demo
+
+/**
+ * @brief call back function of taos_fetch_row_a
+ *
+ * @param param : the third parameter you passed to taos_fetch_row_a
+ * @param res : pointer of TAOS_RES
+ * @param numOfRow : number of rows fetched in this batch. will be 0 if there is no more data.
+ * @return void*
+ */
+void *fetch_row_callback(void *param, TAOS_RES *res, int numOfRow) {
+  printf("numOfRow = %d \n", numOfRow);
+  int         numFields = taos_num_fields(res);
+  TAOS_FIELD *fields = taos_fetch_fields(res);
+  TAOS       *_taos = (TAOS *)param;
+  if (numOfRow > 0) {
+    for (int i = 0; i < numOfRow; ++i) {
+      TAOS_ROW row = taos_fetch_row(res);
+      char     temp[256] = {0};
+      printRow(temp, row, fields, numFields);
+      puts(temp);
+    }
+    taos_fetch_rows_a(res, fetch_row_callback, _taos);
+  } else {
+    printf("no more data, close the connection.\n");
+    taos_free_result(res);
+    taos_close(_taos);
+    taos_cleanup();
+  }
+}
+
+/**
+ * @brief callback function of taos_query_a
+ *
+ * @param param: the fourth parameter you passed to taos_query_a
+ * @param res : the result set
+ * @param code : status code
+ * @return void*
+ */
+void *select_callback(void *param, TAOS_RES *res, int code) {
+  printf("query callback ...\n");
+  TAOS *_taos = (TAOS *)param;
+  if (code == 0 && res) {
+    printHeader(res);
+    taos_fetch_rows_a(res, fetch_row_callback, _taos);
+  } else {
+    printf("failed to execute taos_query. error: %s\n", taos_errstr(res));
+    taos_free_result(res);
+    taos_close(_taos);
+    taos_cleanup();
+    exit(EXIT_FAILURE);
+  }
+}
+
+int main() {
+  TAOS *taos = taos_connect("localhost", "root", "taosdata", "power", 6030);
+  if (taos == NULL) {
+    puts("failed to connect to server");
+    exit(EXIT_FAILURE);
+  }
+  // param one is the connection returned by taos_connect.
+  // param two is the SQL to execute.
+  // param three is the callback function.
+  // param four can be any pointer. It will be passed to your callback function as the first parameter. we use taos
+  // here, because we want to close it after getting data.
+  taos_query_a(taos, "SELECT * FROM meters", select_callback, taos);
+  sleep(1);
+}
+
+// output:
+// query callback ...
+// ts current voltage phase location groupid
+// numOfRow = 8
+// 1538548685000 10.300000 219 0.310000 beijing.chaoyang 2
+// 1538548695000 12.600000 218 0.330000 beijing.chaoyang 2
+// 1538548696800 12.300000 221 0.310000 beijing.chaoyang 2
+// 1538548696650 10.300000 218 0.250000 beijing.chaoyang 3
+// 1538548685500 11.800000 221 0.280000 beijing.haidian 2
+// 1538548696600 13.400000 223 0.290000 beijing.haidian 2
+// 1538548685000 10.800000 223 0.290000 beijing.haidian 3
+// 1538548686500 11.500000 221 0.350000 beijing.haidian 3
+// numOfRow = 0
+// no more data, close the connection.
+// ANCHOR_END: demo
\ No newline at end of file

docs-examples/c/connect_example.c

+// compile with
+// gcc connect_example.c -o connect_example -ltaos
+#include <stdio.h>
+#include <stdlib.h>
+#include "taos.h"
+
+int main() {
+  const char *host = "localhost";
+  const char *user = "root";
+  const char *passwd = "taosdata";
+  // if don't want to connect to a default db, set it to NULL or ""
+  const char *db = NULL;
+  uint16_t    port = 0;  // 0 means use the default port
+  TAOS       *taos = taos_connect(host, user, passwd, db, port);
+  if (taos == NULL) {
+    int   errno = taos_errno(NULL);
+    char *msg = taos_errstr(NULL);
+    printf("%d, %s\n", errno, msg);
+  } else {
+    printf("connected\n");
+    taos_close(taos);
+  }
+  taos_cleanup();
+}

docs-examples/c/error_handle_example.c

+// compile with
+// gcc error_handle_example.c -o error_handle_example -ltaos
+#include <stdio.h>
+#include <stdlib.h>
+#include "taos.h"
+
+int main() {
+  const char *host = "localhost";
+  const char *user = "root";
+  const char *passwd = "taosdata";
+  // if don't want to connect to a default db, set it to NULL or ""
+  const char *db = "notexist";
+  uint16_t    port = 0;  // 0 means use the default port
+  TAOS       *taos = taos_connect(host, user, passwd, db, port);
+  if (taos == NULL) {
+    int errno = taos_errno(NULL);
+    char *msg = taos_errstr(NULL);
+    printf("%d, %s\n", errno, msg);
+  } else {
+    printf("connected\n");
+    taos_close(taos);
+  }
+  taos_cleanup();
+}

docs-examples/c/insert_example.c

+// compile with
+// gcc -o insert_example insert_example.c -ltaos
+#include <stdio.h>
+#include <stdlib.h>
+#include "taos.h"
+
+
+/**
+ * @brief execute sql and print affected rows.
+ * 
+ * @param taos 
+ * @param sql 
+ */
+void executeSQL(TAOS *taos, const char *sql) {
+  TAOS_RES *res = taos_query(taos, sql);
+  int       code = taos_errno(res);
+  if (code != 0) {
+    printf("Error code: %d; Message: %s\n", code, taos_errstr(res));
+    taos_free_result(res);
+    taos_close(taos);
+    exit(EXIT_FAILURE);
+  }
+  int affectedRows = taos_affected_rows(res);
+  printf("affected rows %d\n", affectedRows);
+  taos_free_result(res);
+}
+
+
+
+int main() {
+   TAOS *taos = taos_connect("localhost", "root", "taosdata", NULL, 6030);
+  if (taos == NULL) {
+    printf("failed to connect to server\n");
+    exit(EXIT_FAILURE);
+  }
+  executeSQL(taos, "CREATE DATABASE power");
+  executeSQL(taos, "USE power");
+  executeSQL(taos, "CREATE STABLE meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) TAGS (location BINARY(64), groupId INT)");
+  executeSQL(taos, "INSERT INTO d1001 USING meters TAGS(Beijing.Chaoyang, 2) VALUES ('2018-10-03 14:38:05.000', 10.30000, 219, 0.31000) ('2018-10-03 14:38:15.000', 12.60000, 218, 0.33000) ('2018-10-03 14:38:16.800', 12.30000, 221, 0.31000)"
+                "d1002 USING meters TAGS(Beijing.Chaoyang, 3) VALUES ('2018-10-03 14:38:16.650', 10.30000, 218, 0.25000)"
+                "d1003 USING meters TAGS(Beijing.Haidian, 2) VALUES ('2018-10-03 14:38:05.500', 11.80000, 221, 0.28000) ('2018-10-03 14:38:16.600', 13.40000, 223, 0.29000)"
+                "d1004 USING meters TAGS(Beijing.Haidian, 3) VALUES ('2018-10-03 14:38:05.000', 10.80000, 223, 0.29000) ('2018-10-03 14:38:06.500', 11.50000, 221, 0.35000)");
+  taos_close(taos);
+  taos_cleanup();
+}
+
+// output:
+// affected rows 0
+// affected rows 0
+// affected rows 0
+// affected rows 8
\ No newline at end of file

docs-examples/c/json_protocol_example.c

+// compile with
+// gcc -o json_protocol_example json_protocol_example.c -ltaos
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "taos.h"
+
+void executeSQL(TAOS *taos, const char *sql) {
+  TAOS_RES *res = taos_query(taos, sql);
+  int       code = taos_errno(res);
+  if (code != 0) {
+    printf("%s\n", taos_errstr(res));
+    taos_free_result(res);
+    taos_close(taos);
+    exit(EXIT_FAILURE);
+  }
+  taos_free_result(res);
+}
+
+// ANCHOR: main
+int main() {
+  TAOS *taos = taos_connect("localhost", "root", "taosdata", "", 6030);
+  if (taos == NULL) {
+    printf("failed to connect to server\n");
+    exit(EXIT_FAILURE);
+  }
+  executeSQL(taos, "DROP DATABASE IF EXISTS test");
+  executeSQL(taos, "CREATE DATABASE test");
+  executeSQL(taos, "USE test");
+  char *line =
+      "[{\"metric\": \"meters.current\", \"timestamp\": 1648432611249, \"value\": 10.3, \"tags\": {\"location\": "
+      "\"Beijing.Chaoyang\", \"groupid\": 2}},{\"metric\": \"meters.voltage\", \"timestamp\": 1648432611249, "
+      "\"value\": 219, \"tags\": {\"location\": \"Beijing.Haidian\", \"groupid\": 1}},{\"metric\": \"meters.current\", "
+      "\"timestamp\": 1648432611250, \"value\": 12.6, \"tags\": {\"location\": \"Beijing.Chaoyang\", \"groupid\": "
+      "2}},{\"metric\": \"meters.voltage\", \"timestamp\": 1648432611250, \"value\": 221, \"tags\": {\"location\": "
+      "\"Beijing.Haidian\", \"groupid\": 1}}]";
+
+  char     *lines[] = {line};
+  TAOS_RES *res = taos_schemaless_insert(taos, lines, 1, TSDB_SML_JSON_PROTOCOL, TSDB_SML_TIMESTAMP_NOT_CONFIGURED);
+  if (taos_errno(res) != 0) {
+    printf("failed to insert schema-less data, reason: %s\n", taos_errstr(res));
+  } else {
+    int affectedRow = taos_affected_rows(res);
+    printf("successfully inserted %d rows\n", affectedRow);
+  }
+  taos_free_result(res);
+  taos_close(taos);
+  taos_cleanup();
+}
+// output:
+// successfully inserted 4 rows
+// ANCHOR_END: main

docs-examples/c/line_example.c

+// compile with
+// gcc -o line_example line_example.c -ltaos
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "taos.h"
+
+void executeSQL(TAOS *taos, const char *sql) {
+  TAOS_RES *res = taos_query(taos, sql);
+  int       code = taos_errno(res);
+  if (code != 0) {
+    printf("%s\n", taos_errstr(res));
+    taos_free_result(res);
+    taos_close(taos);
+    exit(EXIT_FAILURE);
+  }
+  taos_free_result(res);
+}
+
+// ANCHOR: main
+int main() {
+  TAOS *taos = taos_connect("localhost", "root", "taosdata", "", 0);
+  if (taos == NULL) {
+    printf("failed to connect to server\n");
+    exit(EXIT_FAILURE);
+  }
+  executeSQL(taos, "DROP DATABASE IF EXISTS test");
+  executeSQL(taos, "CREATE DATABASE test");
+  executeSQL(taos, "USE test");
+  char     *lines[] = {"meters,location=Beijing.Haidian,groupid=2 current=11.8,voltage=221,phase=0.28 1648432611249",
+                   "meters,location=Beijing.Haidian,groupid=2 current=13.4,voltage=223,phase=0.29 1648432611250",
+                   "meters,location=Beijing.Haidian,groupid=3 current=10.8,voltage=223,phase=0.29 1648432611249",
+                   "meters,location=Beijing.Haidian,groupid=3 current=11.3,voltage=221,phase=0.35 1648432611250"};
+  TAOS_RES *res = taos_schemaless_insert(taos, lines, 4, TSDB_SML_LINE_PROTOCOL, TSDB_SML_TIMESTAMP_MILLI_SECONDS);
+  if (taos_errno(res) != 0) {
+    printf("failed to insert schema-less data, reason: %s\n", taos_errstr(res));
+  } else {
+    int affectedRows = taos_affected_rows(res);
+    printf("successfully inserted %d rows\n", affectedRows);
+  }
+  taos_free_result(res);
+  taos_close(taos);
+  taos_cleanup();
+}
+// output:
+// successfully inserted 4 rows
+// ANCHOR_END: main
\ No newline at end of file

docs-examples/c/multi_bind_example.c

+// compile with
+// gcc -o multi_bind_example multi_bind_example.c -ltaos
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "taos.h"
+
+/**
+ * @brief execute sql only and ignore result set
+ *
+ * @param taos
+ * @param sql
+ */
+void executeSQL(TAOS *taos, const char *sql) {
+  TAOS_RES *res = taos_query(taos, sql);
+  int       code = taos_errno(res);
+  if (code != 0) {
+    printf("%s\n", taos_errstr(res));
+    taos_free_result(res);
+    taos_close(taos);
+    exit(EXIT_FAILURE);
+  }
+  taos_free_result(res);
+}
+
+/**
+ * @brief exit program when error occur.
+ *
+ * @param stmt
+ * @param code
+ * @param msg
+ */
+void checkErrorCode(TAOS_STMT *stmt, int code, const char *msg) {
+  if (code != 0) {
+    printf("%s. error: %s\n", msg, taos_stmt_errstr(stmt));
+    taos_stmt_close(stmt);
+    exit(EXIT_FAILURE);
+  }
+}
+
+/**
+ * @brief insert data using stmt API
+ *
+ * @param taos
+ */
+void insertData(TAOS *taos) {
+  // init
+  TAOS_STMT *stmt = taos_stmt_init(taos);
+  // prepare
+  const char *sql = "INSERT INTO ? USING meters TAGS(?, ?) values(?, ?, ?, ?)";
+  int         code = taos_stmt_prepare(stmt, sql, 0);
+  checkErrorCode(stmt, code, "failed to execute taos_stmt_prepare");
+  // bind table name and tags
+  TAOS_BIND tags[2];
+  char     *location = "Beijing.Chaoyang";
+  int       groupId = 2;
+  tags[0].buffer_type = TSDB_DATA_TYPE_BINARY;
+  tags[0].buffer_length = strlen(location);
+  tags[0].length = &tags[0].buffer_length;
+  tags[0].buffer = location;
+  tags[0].is_null = NULL;
+
+  tags[1].buffer_type = TSDB_DATA_TYPE_INT;
+  tags[1].buffer_length = sizeof(int);
+  tags[1].length = &tags[1].buffer_length;
+  tags[1].buffer = &groupId;
+  tags[1].is_null = NULL;
+
+  code = taos_stmt_set_tbname_tags(stmt, "d1001", tags);
+  checkErrorCode(stmt, code, "failed to execute taos_stmt_set_tbname_tags");
+
+  // highlight-start
+  // insert two rows with multi binds
+  TAOS_MULTI_BIND params[4];
+  // values to bind
+  int64_t ts[] = {1648432611249, 1648432611749};
+  float   current[] = {10.3, 12.6};
+  int     voltage[] = {219, 218};
+  float   phase[] = {0.31, 0.33};
+  // is_null array
+  char is_null[2] = {0};
+  // length array
+  int32_t int64Len[2] = {sizeof(int64_t)};
+  int32_t floatLen[2] = {sizeof(float)};
+  int32_t intLen[2] = {sizeof(int)};
+
+  params[0].buffer_type = TSDB_DATA_TYPE_TIMESTAMP;
+  params[0].buffer_length = sizeof(int64_t);
+  params[0].buffer = ts;
+  params[0].length = int64Len;
+  params[0].is_null = is_null;
+  params[0].num = 2;
+
+  params[1].buffer_type = TSDB_DATA_TYPE_FLOAT;
+  params[1].buffer_length = sizeof(float);
+  params[1].buffer = current;
+  params[1].length = floatLen;
+  params[1].is_null = is_null;
+  params[1].num = 2;
+
+  params[2].buffer_type = TSDB_DATA_TYPE_INT;
+  params[2].buffer_length = sizeof(int);
+  params[2].buffer = voltage;
+  params[2].length = intLen;
+  params[2].is_null = is_null;
+  params[2].num = 2;
+
+  params[3].buffer_type = TSDB_DATA_TYPE_FLOAT;
+  params[3].buffer_length = sizeof(float);
+  params[3].buffer = phase;
+  params[3].length = floatLen;
+  params[3].is_null = is_null;
+  params[3].num = 2;
+
+  code = taos_stmt_bind_param_batch(stmt, params); // bind batch
+  checkErrorCode(stmt, code, "failed to execute taos_stmt_bind_param_batch");
+  code = taos_stmt_add_batch(stmt);  // add batch
+  checkErrorCode(stmt, code, "failed to execute taos_stmt_add_batch");
+  // highlight-end
+  // execute
+  code = taos_stmt_execute(stmt);
+  checkErrorCode(stmt, code, "failed to execute taos_stmt_execute");
+  int affectedRows = taos_stmt_affected_rows(stmt);
+  printf("successfully inserted %d rows\n", affectedRows);
+  // close
+  taos_stmt_close(stmt);
+}
+
+int main() {
+  TAOS *taos = taos_connect("localhost", "root", "taosdata", NULL, 6030);
+  if (taos == NULL) {
+    printf("failed to connect to server\n");
+    exit(EXIT_FAILURE);
+  }
+  executeSQL(taos, "DROP DATABASE IF EXISTS power");
+  executeSQL(taos, "CREATE DATABASE power");
+  executeSQL(taos, "USE power");
+  executeSQL(taos,
+             "CREATE STABLE meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) TAGS (location BINARY(64), "
+             "groupId INT)");
+  insertData(taos);
+  taos_close(taos);
+  taos_cleanup();
+}
+
+// output:
+// successfully inserted 2 rows
\ No newline at end of file

docs-examples/c/query_example.c

+// compile with:
+// gcc -o query_example query_example.c -ltaos
+#include <inttypes.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <taos.h>
+
+typedef int16_t VarDataLenT;
+
+#define TSDB_NCHAR_SIZE sizeof(int32_t)
+#define VARSTR_HEADER_SIZE sizeof(VarDataLenT)
+
+#define GET_FLOAT_VAL(x) (*(float *)(x))
+#define GET_DOUBLE_VAL(x) (*(double *)(x))
+
+#define varDataLen(v) ((VarDataLenT *)(v))[0]
+
+int printRow(char *str, TAOS_ROW row, TAOS_FIELD *fields, int numFields) {
+  int  len = 0;
+  char split = ' ';
+
+  for (int i = 0; i < numFields; ++i) {
+    if (i > 0) {
+      str[len++] = split;
+    }
+
+    if (row[i] == NULL) {
+      len += sprintf(str + len, "%s", "NULL");
+      continue;
+    }
+
+    switch (fields[i].type) {
+      case TSDB_DATA_TYPE_TINYINT:
+        len += sprintf(str + len, "%d", *((int8_t *)row[i]));
+        break;
+
+      case TSDB_DATA_TYPE_UTINYINT:
+        len += sprintf(str + len, "%u", *((uint8_t *)row[i]));
+        break;
+
+      case TSDB_DATA_TYPE_SMALLINT:
+        len += sprintf(str + len, "%d", *((int16_t *)row[i]));
+        break;
+
+      case TSDB_DATA_TYPE_USMALLINT:
+        len += sprintf(str + len, "%u", *((uint16_t *)row[i]));
+        break;
+
+      case TSDB_DATA_TYPE_INT:
+        len += sprintf(str + len, "%d", *((int32_t *)row[i]));
+        break;
+
+      case TSDB_DATA_TYPE_UINT:
+        len += sprintf(str + len, "%u", *((uint32_t *)row[i]));
+        break;
+
+      case TSDB_DATA_TYPE_BIGINT:
+        len += sprintf(str + len, "%" PRId64, *((int64_t *)row[i]));
+        break;
+
+      case TSDB_DATA_TYPE_UBIGINT:
+        len += sprintf(str + len, "%" PRIu64, *((uint64_t *)row[i]));
+        break;
+
+      case TSDB_DATA_TYPE_FLOAT: {
+        float fv = 0;
+        fv = GET_FLOAT_VAL(row[i]);
+        len += sprintf(str + len, "%f", fv);
+      } break;
+
+      case TSDB_DATA_TYPE_DOUBLE: {
+        double dv = 0;
+        dv = GET_DOUBLE_VAL(row[i]);
+        len += sprintf(str + len, "%lf", dv);
+      } break;
+
+      case TSDB_DATA_TYPE_BINARY:
+      case TSDB_DATA_TYPE_NCHAR: {
+        int32_t charLen = varDataLen((char *)row[i] - VARSTR_HEADER_SIZE);
+        memcpy(str + len, row[i], charLen);
+        len += charLen;
+      } break;
+
+      case TSDB_DATA_TYPE_TIMESTAMP:
+        len += sprintf(str + len, "%" PRId64, *((int64_t *)row[i]));
+        break;
+
+      case TSDB_DATA_TYPE_BOOL:
+        len += sprintf(str + len, "%d", *((int8_t *)row[i]));
+      default:
+        break;
+    }
+  }
+
+  return len;
+}
+
+/**
+ * @brief print column name and values of each row
+ *
+ * @param res
+ * @return int
+ */
+static int printResult(TAOS_RES *res) {
+  int         numFields = taos_num_fields(res);
+  TAOS_FIELD *fields = taos_fetch_fields(res);
+  char        header[256] = {0};
+  int len = 0;
+  for (int i = 0; i < numFields; ++i) {
+    len += sprintf(header + len, "%s ", fields[i].name);
+  }
+  puts(header);
+
+  TAOS_ROW row = NULL;
+  while ((row = taos_fetch_row(res))) {
+    char temp[256] = {0};
+    printRow(temp, row, fields, numFields);
+    puts(temp);
+  }
+}
+
+int main() {
+  TAOS *taos = taos_connect("localhost", "root", "taosdata", "power", 6030);
+  if (taos == NULL) {
+    puts("failed to connect to server");
+    exit(EXIT_FAILURE);
+  }
+  TAOS_RES *res = taos_query(taos, "SELECT * FROM meters LIMIT 2");
+  if (taos_errno(res) != 0) {
+    printf("failed to execute taos_query. error: %s\n", taos_errstr(res));
+    exit(EXIT_FAILURE);
+  }
+  printResult(res);
+  taos_free_result(res);
+  taos_close(taos);
+  taos_cleanup();
+}
+
+// output:
+// ts current voltage phase location groupid 
+// 1648432611249 10.300000 219 0.310000 Beijing.Chaoyang 2
+// 1648432611749 12.600000 218 0.330000 Beijing.Chaoyang 2
\ No newline at end of file

docs-examples/c/stmt_example.c

+// compile with
+// gcc -o stmt_example stmt_example.c -ltaos
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "taos.h"
+
+/**
+ * @brief execute sql only.
+ * 
+ * @param taos 
+ * @param sql 
+ */
+void executeSQL(TAOS *taos, const char *sql) {
+  TAOS_RES *res = taos_query(taos, sql);
+  int       code = taos_errno(res);
+  if (code != 0) {
+    printf("%s\n", taos_errstr(res));
+    taos_free_result(res);
+    taos_close(taos);
+    exit(EXIT_FAILURE);
+  }
+  taos_free_result(res);
+}
+
+/**
+ * @brief check return status and exit program when error occur.
+ * 
+ * @param stmt 
+ * @param code 
+ * @param msg 
+ */
+void checkErrorCode(TAOS_STMT *stmt, int code, const char* msg) {
+  if (code != 0) {
+    printf("%s. error: %s\n", msg, taos_stmt_errstr(stmt));
+    taos_stmt_close(stmt);
+    exit(EXIT_FAILURE);
+  }
+}
+
+typedef struct {
+  int64_t ts;
+  float current;
+  int voltage;
+  float phase;
+} Row;
+
+/**
+ * @brief insert data using stmt API
+ * 
+ * @param taos 
+ */
+void insertData(TAOS *taos) {
+  // init
+  TAOS_STMT *stmt = taos_stmt_init(taos);
+  // prepare
+  const char *sql = "INSERT INTO ? USING meters TAGS(?, ?) VALUES(?, ?, ?, ?)";
+  int code = taos_stmt_prepare(stmt, sql, 0);
+  checkErrorCode(stmt, code, "failed to execute taos_stmt_prepare");
+  // bind table name and tags
+  TAOS_BIND tags[2];
+  char* location = "Beijing.Chaoyang";
+  int groupId = 2;
+  tags[0].buffer_type = TSDB_DATA_TYPE_BINARY;
+  tags[0].buffer_length = strlen(location);
+  tags[0].length = &tags[0].buffer_length;
+  tags[0].buffer = location;
+  tags[0].is_null = NULL;
+  
+  tags[1].buffer_type = TSDB_DATA_TYPE_INT;
+  tags[1].buffer_length = sizeof(int);
+  tags[1].length = &tags[1].buffer_length;
+  tags[1].buffer = &groupId;
+  tags[1].is_null = NULL;
+
+  code = taos_stmt_set_tbname_tags(stmt, "d1001", tags);
+  checkErrorCode(stmt, code, "failed to execute taos_stmt_set_tbname_tags");
+
+  // insert two rows
+  Row rows[2] = {
+    {1648432611249, 10.3, 219, 0.31},
+    {1648432611749, 12.6, 218, 0.33},
+  };
+
+  TAOS_BIND values[4];
+  values[0].buffer_type = TSDB_DATA_TYPE_TIMESTAMP;
+  values[0].buffer_length = sizeof(int64_t);
+  values[0].length = &values[0].buffer_length;
+  values[0].is_null = NULL;
+
+  values[1].buffer_type = TSDB_DATA_TYPE_FLOAT;
+  values[1].buffer_length = sizeof(float);
+  values[1].length = &values[1].buffer_length;
+  values[1].is_null = NULL;
+
+  values[2].buffer_type = TSDB_DATA_TYPE_INT;
+  values[2].buffer_length = sizeof(int);
+  values[2].length = &values[2].buffer_length;
+  values[2].is_null = NULL;
+
+  values[3].buffer_type = TSDB_DATA_TYPE_FLOAT;
+  values[3].buffer_length = sizeof(float);
+  values[3].length = &values[3].buffer_length;
+  values[3].is_null = NULL;
+
+  for (int i = 0; i < 2; ++i) {
+    values[0].buffer = &rows[i].ts;
+    values[1].buffer = &rows[i].current;
+    values[2].buffer = &rows[i].voltage;
+    values[3].buffer = &rows[i].phase;
+    code = taos_stmt_bind_param(stmt, values); // bind param
+    checkErrorCode(stmt, code, "failed to execute taos_stmt_bind_param");
+    code = taos_stmt_add_batch(stmt); // add batch
+    checkErrorCode(stmt, code, "failed to execute taos_stmt_add_batch");
+  }
+  // execute
+  code = taos_stmt_execute(stmt);
+  checkErrorCode(stmt, code, "failed to execute taos_stmt_execute");
+  int affectedRows = taos_stmt_affected_rows(stmt);
+  printf("successfully inserted %d rows\n", affectedRows);
+  // close
+  taos_stmt_close(stmt);
+}
+
+int main() {
+  TAOS *taos = taos_connect("localhost", "root", "taosdata", NULL, 6030);
+  if (taos == NULL) {
+    printf("failed to connect to server\n");
+    exit(EXIT_FAILURE);
+  }
+  executeSQL(taos, "CREATE DATABASE power");
+  executeSQL(taos, "USE power");
+  executeSQL(taos, "CREATE STABLE meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) TAGS (location BINARY(64), groupId INT)");
+  insertData(taos);
+  taos_close(taos);
+  taos_cleanup();
+}
+
+
+// output:
+// successfully inserted 2 rows
\ No newline at end of file

docs-examples/c/subscribe_demo.c

+// A simple demo for asynchronous subscription.
+// compile with:
+// gcc -o subscribe_demo subscribe_demo.c -ltaos
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <taos.h>
+
+int nTotalRows;
+
+/**
+ * @brief callback function of subscription.
+ *
+ * @param tsub
+ * @param res
+ * @param param. the additional parameter passed to  taos_subscribe
+ * @param code. error code
+ */
+void subscribe_callback(TAOS_SUB* tsub, TAOS_RES* res, void* param, int code) {
+  if (code != 0) {
+    printf("error: %d\n", code);
+    exit(EXIT_FAILURE);
+  }
+
+  TAOS_ROW    row = NULL;
+  int         num_fields = taos_num_fields(res);
+  TAOS_FIELD* fields = taos_fetch_fields(res);
+  int         nRows = 0;
+
+  while ((row = taos_fetch_row(res))) {
+    char buf[4096] = {0};
+    taos_print_row(buf, row, fields, num_fields);
+    puts(buf);
+    nRows++;
+  }
+
+  nTotalRows += nRows;
+  printf("%d rows consumed.\n", nRows);
+}
+
+int main() {
+  TAOS* taos = taos_connect("localhost", "root", "taosdata", NULL, 6030);
+  if (taos == NULL) {
+    printf("failed to connect to server\n");
+    exit(EXIT_FAILURE);
+  }
+
+  int         restart = 1;  // if the topic already exists, where to subscribe from the begin.
+  const char* topic = "topic-meter-current-bg-10";
+  const char* sql = "select * from power.meters where current > 10";
+  void*       param = NULL;     // additional parameter.
+  int         interval = 2000;  // consumption interval in microseconds.
+  TAOS_SUB*   tsub = taos_subscribe(taos, restart, topic, sql, subscribe_callback, NULL, interval);
+
+  // wait for insert from others process. you can open TDengine CLI to insert some records for test.
+  
+  getchar();  // press Enter to stop
+
+  printf("total rows consumed: %d\n", nTotalRows);
+  int keep = 0;  // whether to keep subscribe process
+  taos_unsubscribe(tsub, keep);
+
+  taos_close(taos);
+  taos_cleanup();
+}

docs-examples/c/telnet_line_example.c

+// compile with
+// gcc -o telnet_line_example telnet_line_example.c -ltaos
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "taos.h"
+
+void executeSQL(TAOS *taos, const char *sql) {
+  TAOS_RES *res = taos_query(taos, sql);
+  int       code = taos_errno(res);
+  if (code != 0) {
+    printf("%s\n", taos_errstr(res));
+    taos_free_result(res);
+    taos_close(taos);
+    exit(EXIT_FAILURE);
+  }
+  taos_free_result(res);
+}
+
+// ANCHOR: main
+int main() {
+  TAOS *taos = taos_connect("localhost", "root", "taosdata", "", 6030);
+  if (taos == NULL) {
+    printf("failed to connect to server\n");
+    exit(EXIT_FAILURE);
+  }
+  executeSQL(taos, "DROP DATABASE IF EXISTS test");
+  executeSQL(taos, "CREATE DATABASE test");
+  executeSQL(taos, "USE test");
+  char *lines[] = {
+      "meters.current 1648432611249 10.3 location=Beijing.Chaoyang groupid=2",
+      "meters.current 1648432611250 12.6 location=Beijing.Chaoyang groupid=2",
+      "meters.current 1648432611249 10.8 location=Beijing.Haidian groupid=3",
+      "meters.current 1648432611250 11.3 location=Beijing.Haidian groupid=3",
+      "meters.voltage 1648432611249 219 location=Beijing.Chaoyang groupid=2",
+      "meters.voltage 1648432611250 218 location=Beijing.Chaoyang groupid=2",
+      "meters.voltage 1648432611249 221 location=Beijing.Haidian groupid=3",
+      "meters.voltage 1648432611250 217 location=Beijing.Haidian groupid=3",
+  };
+  TAOS_RES *res = taos_schemaless_insert(taos, lines, 8, TSDB_SML_TELNET_PROTOCOL, TSDB_SML_TIMESTAMP_NOT_CONFIGURED);
+  if (taos_errno(res) != 0) {
+    printf("failed to insert schema-less data, reason: %s\n", taos_errstr(res));
+  } else {
+    int affectedRow = taos_affected_rows(res);
+    printf("successfully inserted %d rows\n", affectedRow);
+  }
+
+  taos_free_result(res);
+  taos_close(taos);
+  taos_cleanup();
+}
+// output:
+// successfully inserted 8 rows
+// ANCHOR_END: main

docs-examples/csharp/.gitignore

+bin
+obj
+.vs
+*.sln
\ No newline at end of file

docs-examples/csharp/AsyncQueryExample.cs

+using TDengineDriver;
+using System.Runtime.InteropServices;
+
+namespace TDengineExample
+{
+    public class AsyncQueryExample
+    {
+        static void Main()
+        {
+            IntPtr conn = GetConnection();
+            QueryAsyncCallback queryAsyncCallback = new QueryAsyncCallback(QueryCallback);
+            TDengine.QueryAsync(conn, "select * from meters", queryAsyncCallback, IntPtr.Zero);
+            Thread.Sleep(2000);
+            TDengine.Close(conn);
+            TDengine.Cleanup();
+        }
+
+        static void QueryCallback(IntPtr param, IntPtr taosRes, int code)
+        {
+            if (code == 0 && taosRes != IntPtr.Zero)
+            {
+                FetchRowAsyncCallback fetchRowAsyncCallback = new FetchRowAsyncCallback(FetchRowCallback);
+                TDengine.FetchRowAsync(taosRes, fetchRowAsyncCallback, param);
+            }
+            else
+            {
+                Console.WriteLine($"async query data failed, failed code {code}");
+            }
+        }
+
+        static void FetchRowCallback(IntPtr param, IntPtr taosRes, int numOfRows)
+        {
+            if (numOfRows > 0)
+            {
+                Console.WriteLine($"{numOfRows} rows async retrieved");
+                DisplayRes(taosRes);
+                TDengine.FetchRowAsync(taosRes, FetchRowCallback, param);
+            }
+            else
+            {
+                if (numOfRows == 0)
+                {
+                    Console.WriteLine("async retrieve complete.");
+
+                }
+                else
+                {
+                    Console.WriteLine($"FetchRowAsync callback error, error code {numOfRows}");
+                }
+                TDengine.FreeResult(taosRes);
+            }
+        }
+
+        public static void DisplayRes(IntPtr res)
+        {
+            if (!IsValidResult(res))
+            {
+                TDengine.Cleanup();
+                System.Environment.Exit(1);
+            }
+
+            List<TDengineMeta> metaList = TDengine.FetchFields(res);
+            int fieldCount = metaList.Count;
+            // metaList.ForEach((item) => { Console.Write("{0} ({1}) \t|\t", item.name, item.size); });
+
+            List<object> dataList = QueryRes(res, metaList);
+            for (int index = 0; index < dataList.Count; index++)
+            {
+                if (index % fieldCount == 0 && index != 0)
+                {
+                    Console.WriteLine("");
+                }
+                Console.Write("{0} \t|\t", dataList[index].ToString());
+
+            }
+            Console.WriteLine("");
+        }
+
+        public static bool IsValidResult(IntPtr res)
+        {
+            if ((res == IntPtr.Zero) || (TDengine.ErrorNo(res) != 0))
+            {
+                if (res != IntPtr.Zero)
+                {
+                    Console.Write("reason: " + TDengine.Error(res));
+                    return false;
+                }
+                Console.WriteLine("");
+                return false;
+            }
+            return true;
+        }
+
+        private static List<object> QueryRes(IntPtr res, List<TDengineMeta> meta)
+        {
+            IntPtr taosRow;
+            List<object> dataRaw = new();
+            while ((taosRow = TDengine.FetchRows(res)) != IntPtr.Zero)
+            {
+                dataRaw.AddRange(FetchRow(taosRow, res));
+            }
+            if (TDengine.ErrorNo(res) != 0)
+            {
+                Console.Write("Query is not complete, Error {0} {1}", TDengine.ErrorNo(res), TDengine.Error(res));
+            }
+            TDengine.FreeResult(res);
+            Console.WriteLine("");
+            return dataRaw;
+        }
+
+        public static List<object> FetchRow(IntPtr taosRow, IntPtr taosRes)//, List<TDengineMeta> metaList, int numOfFiled
+        {
+            List<TDengineMeta> metaList = TDengine.FetchFields(taosRes);
+            int numOfFiled = TDengine.FieldCount(taosRes);
+
+
+            List<object> dataRaw = new();
+
+            IntPtr colLengthPrt = TDengine.FetchLengths(taosRes);
+            int[] colLengthArr = new int[numOfFiled];
+            Marshal.Copy(colLengthPrt, colLengthArr, 0, numOfFiled);
+
+            for (int i = 0; i < numOfFiled; i++)
+            {
+                TDengineMeta meta = metaList[i];
+                IntPtr data = Marshal.ReadIntPtr(taosRow, IntPtr.Size * i);
+
+                if (data == IntPtr.Zero)
+                {
+                    dataRaw.Add("NULL");
+                    continue;
+                }
+                switch ((TDengineDataType)meta.type)
+                {
+                    case TDengineDataType.TSDB_DATA_TYPE_BOOL:
+                        bool v1 = Marshal.ReadByte(data) != 0;
+                        dataRaw.Add(v1);
+                        break;
+                    case TDengineDataType.TSDB_DATA_TYPE_TINYINT:
+                        sbyte v2 = (sbyte)Marshal.ReadByte(data);
+                        dataRaw.Add(v2);
+                        break;
+                    case TDengineDataType.TSDB_DATA_TYPE_SMALLINT:
+                        short v3 = Marshal.ReadInt16(data);
+                        dataRaw.Add(v3);
+                        break;
+                    case TDengineDataType.TSDB_DATA_TYPE_INT:
+                        int v4 = Marshal.ReadInt32(data);
+                        dataRaw.Add(v4);
+                        break;
+                    case TDengineDataType.TSDB_DATA_TYPE_BIGINT:
+                        long v5 = Marshal.ReadInt64(data);
+                        dataRaw.Add(v5);
+                        break;
+                    case TDengineDataType.TSDB_DATA_TYPE_FLOAT:
+                        float v6 = (float)Marshal.PtrToStructure(data, typeof(float));
+                        dataRaw.Add(v6);
+                        break;
+                    case TDengineDataType.TSDB_DATA_TYPE_DOUBLE:
+                        double v7 = (double)Marshal.PtrToStructure(data, typeof(double));
+                        dataRaw.Add(v7);
+                        break;
+                    case TDengineDataType.TSDB_DATA_TYPE_BINARY:
+                        string v8 = Marshal.PtrToStringUTF8(data, colLengthArr[i]);
+                        dataRaw.Add(v8);
+                        break;
+                    case TDengineDataType.TSDB_DATA_TYPE_TIMESTAMP:
+                        long v9 = Marshal.ReadInt64(data);
+                        dataRaw.Add(v9);
+                        break;
+                    case TDengineDataType.TSDB_DATA_TYPE_NCHAR:
+                        string v10 = Marshal.PtrToStringUTF8(data, colLengthArr[i]);
+                        dataRaw.Add(v10);
+                        break;
+                    case TDengineDataType.TSDB_DATA_TYPE_UTINYINT:
+                        byte v12 = Marshal.ReadByte(data);
+                        dataRaw.Add(v12.ToString());
+                        break;
+                    case TDengineDataType.TSDB_DATA_TYPE_USMALLINT:
+                        ushort v13 = (ushort)Marshal.ReadInt16(data);
+                        dataRaw.Add(v13);
+                        break;
+                    case TDengineDataType.TSDB_DATA_TYPE_UINT:
+                        uint v14 = (uint)Marshal.ReadInt32(data);
+                        dataRaw.Add(v14);
+                        break;
+                    case TDengineDataType.TSDB_DATA_TYPE_UBIGINT:
+                        ulong v15 = (ulong)Marshal.ReadInt64(data);
+                        dataRaw.Add(v15);
+                        break;
+                    case TDengineDataType.TSDB_DATA_TYPE_JSONTAG:
+                        string v16 = Marshal.PtrToStringUTF8(data, colLengthArr[i]);
+                        dataRaw.Add(v16);
+                        break;
+                    default:
+                        dataRaw.Add("nonsupport data type");
+                        break;
+                }
+
+            }
+            return dataRaw;
+        }
+
+        static IntPtr GetConnection()
+        {
+            string host = "localhost";
+            short port = 6030;
+            string username = "root";
+            string password = "taosdata";
+            string dbname = "power";
+            var conn = TDengine.Connect(host, username, password, dbname, port);
+            if (conn == IntPtr.Zero)
+            {
+                Console.WriteLine("Connect to TDengine failed");
+                Environment.Exit(0);
+            }
+            else
+            {
+                Console.WriteLine("Connect to TDengine success");
+            }
+            return conn;
+        }
+    }
+}
+
+//output:
+//Connect to TDengine success
+//8 rows async retrieved
+
+//1538548685000   |       10.3    |       219     |       0.31    |       beijing.chaoyang        |       2       |
+//1538548695000   |       12.6    |       218     |       0.33    |       beijing.chaoyang        |       2       |
+//1538548696800   |       12.3    |       221     |       0.31    |       beijing.chaoyang        |       2       |
+//1538548696650   |       10.3    |       218     |       0.25    |       beijing.chaoyang        |       3       |
+//1538548685500   |       11.8    |       221     |       0.28    |       beijing.haidian         |       2       |
+//1538548696600   |       13.4    |       223     |       0.29    |       beijing.haidian         |       2       |
+//1538548685000   |       10.8    |       223     |       0.29    |       beijing.haidian         |       3       |
+//1538548686500   |       11.5    |       221     |       0.35    |       beijing.haidian         |       3       |
+//async retrieve complete.
\ No newline at end of file

docs-examples/csharp/ConnectExample.cs

+using TDengineDriver;
+
+namespace TDengineExample
+{
+
+    internal class ConnectExample
+    {
+        static void Main(String[] args)
+        {
+            string host = "localhost";
+            short port = 6030;
+            string username = "root";
+            string password = "taosdata";
+            string dbname = "";
+
+            var conn = TDengine.Connect(host, username, password, dbname, port);
+            if (conn == IntPtr.Zero)
+            {
+                Console.WriteLine("Connect to TDengine failed");
+            }
+            else
+            {
+                Console.WriteLine("Connect to TDengine success");
+            }
+            TDengine.Close(conn);
+            TDengine.Cleanup();
+        }
+    }
+}

docs-examples/csharp/InfluxDBLineExample.cs

+using TDengineDriver;
+
+namespace TDengineExample
+{
+    internal class InfluxDBLineExample
+    {
+        static void Main()
+        {
+            IntPtr conn = GetConnection();
+            PrepareDatabase(conn);
+            string[] lines = {
+                "meters,location=Beijing.Haidian,groupid=2 current=11.8,voltage=221,phase=0.28 1648432611249",
+                "meters,location=Beijing.Haidian,groupid=2 current=13.4,voltage=223,phase=0.29 1648432611250",
+                "meters,location=Beijing.Haidian,groupid=3 current=10.8,voltage=223,phase=0.29 1648432611249",
+                "meters,location=Beijing.Haidian,groupid=3 current=11.3,voltage=221,phase=0.35 1648432611250"
+            };
+            IntPtr res = TDengine.SchemalessInsert(conn, lines, lines.Length, (int)TDengineSchemalessProtocol.TSDB_SML_LINE_PROTOCOL, (int)TDengineSchemalessPrecision.TSDB_SML_TIMESTAMP_MILLI_SECONDS);
+            if (TDengine.ErrorNo(res) != 0)
+            {
+                Console.WriteLine("SchemalessInsert failed since " + TDengine.Error(res));
+                ExitProgram(conn, 1);
+            }
+            else
+            {
+                int affectedRows = TDengine.AffectRows(res);
+                Console.WriteLine($"SchemalessInsert success, affected {affectedRows} rows");
+            }
+            TDengine.FreeResult(res);
+            ExitProgram(conn, 0);
+
+        }
+        static IntPtr GetConnection()
+        {
+            string host = "localhost";
+            short port = 6030;
+            string username = "root";
+            string password = "taosdata";
+            string dbname = "";
+            var conn = TDengine.Connect(host, username, password, dbname, port);
+            if (conn == IntPtr.Zero)
+            {
+                Console.WriteLine("Connect to TDengine failed");
+                TDengine.Cleanup();
+                Environment.Exit(1);
+            }
+            else
+            {
+                Console.WriteLine("Connect to TDengine success");
+            }
+            return conn;
+        }
+
+        static void PrepareDatabase(IntPtr conn)
+        {
+            IntPtr res = TDengine.Query(conn, "CREATE DATABASE test");
+            if (TDengine.ErrorNo(res) != 0)
+            {
+                Console.WriteLine("failed to create database, reason: " + TDengine.Error(res));
+                ExitProgram(conn, 1);
+            }
+            res = TDengine.Query(conn, "USE test");
+            if (TDengine.ErrorNo(res) != 0)
+            {
+                Console.WriteLine("failed to change database, reason: " + TDengine.Error(res));
+                ExitProgram(conn, 1);
+            }
+        }
+
+        static void ExitProgram(IntPtr conn, int exitCode)
+        {
+            TDengine.Close(conn);
+            TDengine.Cleanup();
+            Environment.Exit(exitCode);
+        }
+    }
+
+}

docs-examples/csharp/OptsJsonExample.cs

+using TDengineDriver;
+
+namespace TDengineExample
+{
+    internal class OptsJsonExample
+    {
+        static void Main()
+        {
+            IntPtr conn = GetConnection();
+            PrepareDatabase(conn);
+            string[] lines = { "[{\"metric\": \"meters.current\", \"timestamp\": 1648432611249, \"value\": 10.3, \"tags\": {\"location\": \"Beijing.Chaoyang\", \"groupid\": 2}}," +
+                " {\"metric\": \"meters.voltage\", \"timestamp\": 1648432611249, \"value\": 219, \"tags\": {\"location\": \"Beijing.Haidian\", \"groupid\": 1}}, " +
+                "{\"metric\": \"meters.current\", \"timestamp\": 1648432611250, \"value\": 12.6, \"tags\": {\"location\": \"Beijing.Chaoyang\", \"groupid\": 2}}," +
+                " {\"metric\": \"meters.voltage\", \"timestamp\": 1648432611250, \"value\": 221, \"tags\": {\"location\": \"Beijing.Haidian\", \"groupid\": 1}}]"
+            };
+
+            IntPtr res = TDengine.SchemalessInsert(conn, lines, 1, (int)TDengineSchemalessProtocol.TSDB_SML_JSON_PROTOCOL, (int)TDengineSchemalessPrecision.TSDB_SML_TIMESTAMP_NOT_CONFIGURED);
+            if (TDengine.ErrorNo(res) != 0)
+            {
+                Console.WriteLine("SchemalessInsert failed since " + TDengine.Error(res));
+                ExitProgram(conn, 1);
+            }
+            else
+            {
+                int affectedRows = TDengine.AffectRows(res);
+                Console.WriteLine($"SchemalessInsert success, affected {affectedRows} rows");
+            }
+            TDengine.FreeResult(res);
+            ExitProgram(conn, 0);
+
+        }
+        static IntPtr GetConnection()
+        {
+            string host = "localhost";
+            short port = 6030;
+            string username = "root";
+            string password = "taosdata";
+            string dbname = "";
+            var conn = TDengine.Connect(host, username, password, dbname, port);
+            if (conn == IntPtr.Zero)
+            {
+                Console.WriteLine("Connect to TDengine failed");
+                TDengine.Cleanup();
+                Environment.Exit(1);
+            }
+            else
+            {
+                Console.WriteLine("Connect to TDengine success");
+            }
+            return conn;
+        }
+
+        static void PrepareDatabase(IntPtr conn)
+        {
+            IntPtr res = TDengine.Query(conn, "CREATE DATABASE test");
+            if (TDengine.ErrorNo(res) != 0)
+            {
+                Console.WriteLine("failed to create database, reason: " + TDengine.Error(res));
+                ExitProgram(conn, 1);
+            }
+            res = TDengine.Query(conn, "USE test");
+            if (TDengine.ErrorNo(res) != 0)
+            {
+                Console.WriteLine("failed to change database, reason: " + TDengine.Error(res));
+                ExitProgram(conn, 1);
+            }
+        }
+
+        static void ExitProgram(IntPtr conn, int exitCode)
+        {
+            TDengine.Close(conn);
+            TDengine.Cleanup();
+            Environment.Exit(exitCode);
+        }
+    }
+}

docs-examples/csharp/OptsTelnetExample.cs

+using TDengineDriver;
+
+namespace TDengineExample
+{
+    internal class OptsTelnetExample
+    {
+        static void Main()
+        {
+            IntPtr conn = GetConnection();
+            PrepareDatabase(conn);
+            string[] lines = {
+                "meters.current 1648432611249 10.3 location=Beijing.Chaoyang groupid=2",
+                "meters.current 1648432611250 12.6 location=Beijing.Chaoyang groupid=2",
+                "meters.current 1648432611249 10.8 location=Beijing.Haidian groupid=3",
+                "meters.current 1648432611250 11.3 location=Beijing.Haidian groupid=3",
+                "meters.voltage 1648432611249 219 location=Beijing.Chaoyang groupid=2",
+                "meters.voltage 1648432611250 218 location=Beijing.Chaoyang groupid=2",
+                "meters.voltage 1648432611249 221 location=Beijing.Haidian groupid=3",
+                "meters.voltage 1648432611250 217 location=Beijing.Haidian groupid=3",
+            };
+            IntPtr res = TDengine.SchemalessInsert(conn, lines, lines.Length, (int)TDengineSchemalessProtocol.TSDB_SML_TELNET_PROTOCOL, (int)TDengineSchemalessPrecision.TSDB_SML_TIMESTAMP_NOT_CONFIGURED);
+            if (TDengine.ErrorNo(res) != 0)
+            {
+                Console.WriteLine("SchemalessInsert failed since " + TDengine.Error(res));
+                ExitProgram(conn, 1);
+            }
+            else
+            {
+                int affectedRows = TDengine.AffectRows(res);
+                Console.WriteLine($"SchemalessInsert success, affected {affectedRows} rows");
+            }
+            TDengine.FreeResult(res);
+            ExitProgram(conn, 0);
+
+        }
+        static IntPtr GetConnection()
+        {
+            string host = "localhost";
+            short port = 6030;
+            string username = "root";
+            string password = "taosdata";
+            string dbname = "";
+            var conn = TDengine.Connect(host, username, password, dbname, port);
+            if (conn == IntPtr.Zero)
+            {
+                Console.WriteLine("Connect to TDengine failed");
+                TDengine.Cleanup();
+                Environment.Exit(1);
+            }
+            else
+            {
+                Console.WriteLine("Connect to TDengine success");
+            }
+            return conn;
+        }
+
+        static void PrepareDatabase(IntPtr conn)
+        {
+            IntPtr res = TDengine.Query(conn, "CREATE DATABASE test");
+            if (TDengine.ErrorNo(res) != 0)
+            {
+                Console.WriteLine("failed to create database, reason: " + TDengine.Error(res));
+                ExitProgram(conn, 1);
+            }
+            res = TDengine.Query(conn, "USE test");
+            if (TDengine.ErrorNo(res) != 0)
+            {
+                Console.WriteLine("failed to change database, reason: " + TDengine.Error(res));
+                ExitProgram(conn, 1);
+            }
+        }
+
+        static void ExitProgram(IntPtr conn, int exitCode)
+        {
+            TDengine.Close(conn);
+            TDengine.Cleanup();
+            Environment.Exit(exitCode);
+        }
+    }
+}

docs-examples/csharp/QueryExample.cs

+using TDengineDriver;
+using System.Runtime.InteropServices;
+
+namespace TDengineExample
+{
+    internal class QueryExample
+    {
+        static void Main()
+        {
+            IntPtr conn = GetConnection();
+            // run query
+            IntPtr res = TDengine.Query(conn, "SELECT * FROM test.meters LIMIT 2");
+            if (TDengine.ErrorNo(res) != 0)
+            {
+                Console.WriteLine("Failed to query since: " + TDengine.Error(res));
+                TDengine.Close(conn);
+                TDengine.Cleanup();
+                return;
+            }
+
+            // get filed count
+            int fieldCount = TDengine.FieldCount(res);
+            Console.WriteLine("fieldCount=" + fieldCount);
+
+            // print column names
+            List<TDengineMeta> metas = TDengine.FetchFields(res);
+            for (int i = 0; i < metas.Count; i++)
+            {
+                Console.Write(metas[i].name + "\t");
+            }
+            Console.WriteLine();
+
+            // print values
+            IntPtr row;
+            while ((row = TDengine.FetchRows(res)) != IntPtr.Zero)
+            {
+                List<TDengineMeta> metaList = TDengine.FetchFields(res);
+                int numOfFiled = TDengine.FieldCount(res);
+
+                List<String> dataRaw = new List<string>();
+
+                IntPtr colLengthPrt = TDengine.FetchLengths(res);
+                int[] colLengthArr = new int[numOfFiled];
+                Marshal.Copy(colLengthPrt, colLengthArr, 0, numOfFiled);
+
+                for (int i = 0; i < numOfFiled; i++)
+                {
+                    TDengineMeta meta = metaList[i];
+                    IntPtr data = Marshal.ReadIntPtr(row, IntPtr.Size * i);
+
+                    if (data == IntPtr.Zero)
+                    {
+                        Console.Write("NULL\t");
+                        continue;
+                    }
+                    switch ((TDengineDataType)meta.type)
+                    {
+                        case TDengineDataType.TSDB_DATA_TYPE_BOOL:
+                            bool v1 = Marshal.ReadByte(data) == 0 ? false : true;
+                            Console.Write(v1.ToString() + "\t");
+                            break;
+                        case TDengineDataType.TSDB_DATA_TYPE_TINYINT:
+                            sbyte v2 = (sbyte)Marshal.ReadByte(data);
+                            Console.Write(v2.ToString() + "\t");
+                            break;
+                        case TDengineDataType.TSDB_DATA_TYPE_SMALLINT:
+                            short v3 = Marshal.ReadInt16(data);
+                            Console.Write(v3.ToString() + "\t");
+                            break;
+                        case TDengineDataType.TSDB_DATA_TYPE_INT:
+                            int v4 = Marshal.ReadInt32(data);
+                            Console.Write(v4.ToString() + "\t");
+                            break;
+                        case TDengineDataType.TSDB_DATA_TYPE_BIGINT:
+                            long v5 = Marshal.ReadInt64(data);
+                            Console.Write(v5.ToString() + "\t");
+                            break;
+                        case TDengineDataType.TSDB_DATA_TYPE_FLOAT:
+                            float v6 = (float)Marshal.PtrToStructure(data, typeof(float));
+                            Console.Write(v6.ToString() + "\t");
+                            break;
+                        case TDengineDataType.TSDB_DATA_TYPE_DOUBLE:
+                            double v7 = (double)Marshal.PtrToStructure(data, typeof(double));
+                            Console.Write(v7.ToString() + "\t");
+                            break;
+                        case TDengineDataType.TSDB_DATA_TYPE_BINARY:
+                            string v8 = Marshal.PtrToStringUTF8(data, colLengthArr[i]);
+                            Console.Write(v8 + "\t");
+                            break;
+                        case TDengineDataType.TSDB_DATA_TYPE_TIMESTAMP:
+                            long v9 = Marshal.ReadInt64(data);
+                            Console.Write(v9.ToString() + "\t");
+                            break;
+                        case TDengineDataType.TSDB_DATA_TYPE_NCHAR:
+                            string v10 = Marshal.PtrToStringUTF8(data, colLengthArr[i]);
+                            Console.Write(v10 + "\t");
+                            break;
+                        case TDengineDataType.TSDB_DATA_TYPE_UTINYINT:
+                            byte v12 = Marshal.ReadByte(data);
+                            Console.Write(v12.ToString() + "\t");
+                            break;
+                        case TDengineDataType.TSDB_DATA_TYPE_USMALLINT:
+                            ushort v13 = (ushort)Marshal.ReadInt16(data);
+                            Console.Write(v13.ToString() + "\t");
+                            break;
+                        case TDengineDataType.TSDB_DATA_TYPE_UINT:
+                            uint v14 = (uint)Marshal.ReadInt32(data);
+                            Console.Write(v14.ToString() + "\t");
+                            break;
+                        case TDengineDataType.TSDB_DATA_TYPE_UBIGINT:
+                            ulong v15 = (ulong)Marshal.ReadInt64(data);
+                            Console.Write(v15.ToString() + "\t");
+                            break;
+                        case TDengineDataType.TSDB_DATA_TYPE_JSONTAG:
+                            string v16 = Marshal.PtrToStringUTF8(data, colLengthArr[i]);
+                            Console.Write(v16 + "\t");
+                            break;
+                        default:
+                            Console.Write("nonsupport data type value");
+                            break;
+                    }
+
+                }
+                Console.WriteLine();
+            }
+            if (TDengine.ErrorNo(res) != 0)
+            {
+                Console.WriteLine($"Query is not complete, Error {TDengine.ErrorNo(res)} {TDengine.Error(res)}");
+            }
+            // exit
+            TDengine.FreeResult(res);
+            TDengine.Close(conn);
+            TDengine.Cleanup();
+        }
+        static IntPtr GetConnection()
+        {
+            string host = "localhost";
+            short port = 6030;
+            string username = "root";
+            string password = "taosdata";
+            string dbname = "power";
+            var conn = TDengine.Connect(host, username, password, dbname, port);
+            if (conn == IntPtr.Zero)
+            {
+                Console.WriteLine("Connect to TDengine failed");
+                System.Environment.Exit(0);
+            }
+            else
+            {
+                Console.WriteLine("Connect to TDengine success");
+            }
+            return conn;
+        }
+    }
+}
+
+// output:
+// Connect to TDengine success
+// fieldCount=6
+// ts      current voltage phase   location        groupid
+// 1648432611249   10.3    219     0.31    Beijing.Chaoyang        2
+// 1648432611749   12.6    218     0.33    Beijing.Chaoyang        2
\ No newline at end of file

docs-examples/csharp/SQLInsertExample.cs

+using TDengineDriver;
+
+
+namespace TDengineExample
+{
+    internal class SQLInsertExample
+    {
+
+        static void Main()
+        {
+            IntPtr conn = GetConnection();
+            IntPtr res = TDengine.Query(conn, "CREATE DATABASE power");
+            CheckRes(conn, res, "failed to create database");
+            res = TDengine.Query(conn, "USE power");
+            CheckRes(conn, res, "failed to change database");
+            res = TDengine.Query(conn, "CREATE STABLE power.meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) TAGS (location BINARY(64), groupId INT)");
+            CheckRes(conn, res, "failed to create stable");
+            var sql = "INSERT INTO d1001 USING meters TAGS(Beijing.Chaoyang, 2) VALUES ('2018-10-03 14:38:05.000', 10.30000, 219, 0.31000) ('2018-10-03 14:38:15.000', 12.60000, 218, 0.33000) ('2018-10-03 14:38:16.800', 12.30000, 221, 0.31000) " +
+                        "d1002 USING power.meters TAGS(Beijing.Chaoyang, 3) VALUES('2018-10-03 14:38:16.650', 10.30000, 218, 0.25000) " +
+                        "d1003 USING power.meters TAGS(Beijing.Haidian, 2) VALUES('2018-10-03 14:38:05.500', 11.80000, 221, 0.28000)('2018-10-03 14:38:16.600', 13.40000, 223, 0.29000) " +
+                        "d1004 USING power.meters TAGS(Beijing.Haidian, 3) VALUES('2018-10-03 14:38:05.000', 10.80000, 223, 0.29000)('2018-10-03 14:38:06.500', 11.50000, 221, 0.35000)";
+            res = TDengine.Query(conn, sql);
+            CheckRes(conn, res, "failed to insert data");
+            int affectedRows = TDengine.AffectRows(res);
+            Console.WriteLine("affectedRows " + affectedRows);
+            ExitProgram(conn, 0);
+        }
+
+        static IntPtr GetConnection()
+        {
+            string host = "localhost";
+            short port = 6030;
+            string username = "root";
+            string password = "taosdata";
+            string dbname = "";
+            var conn = TDengine.Connect(host, username, password, dbname, port);
+            if (conn == IntPtr.Zero)
+            {
+                Console.WriteLine("Connect to TDengine failed");
+                Environment.Exit(0);
+            }
+            else
+            {
+                Console.WriteLine("Connect to TDengine success");
+            }
+            return conn;
+        }
+
+        static void CheckRes(IntPtr conn, IntPtr res, String errorMsg)
+        {
+            if (TDengine.ErrorNo(res) != 0)
+            {
+                Console.Write(errorMsg + " since: " + TDengine.Error(res));
+                ExitProgram(conn, 1);
+            }
+        }
+
+        static void ExitProgram(IntPtr conn, int exitCode)
+        {
+            TDengine.Close(conn);
+            TDengine.Cleanup();
+            Environment.Exit(exitCode);
+        }
+    }
+}
+
+// output:
+// Connect to TDengine success
+// affectedRows 8

docs-examples/csharp/StmtInsertExample.cs

+using TDengineDriver;
+
+namespace TDengineExample
+{
+    internal class StmtInsertExample
+    {
+        private static IntPtr conn;
+        private static IntPtr stmt;
+        static void Main()
+        {
+            conn = GetConnection();
+            PrepareSTable();
+            // 1. init and prepare
+            stmt = TDengine.StmtInit(conn);
+            if (stmt == IntPtr.Zero)
+            {
+                Console.WriteLine("failed to init stmt, " + TDengine.Error(stmt));
+                ExitProgram();
+            }
+            int res = TDengine.StmtPrepare(stmt, "INSERT INTO ? USING meters TAGS(?, ?) VALUES(?, ?, ?, ?)");
+            CheckStmtRes(res, "failed to prepare stmt");
+
+            // 2. bind table name and tags
+            TAOS_BIND[] tags = new TAOS_BIND[2] { TaosBind.BindBinary("Beijing.Chaoyang"), TaosBind.BindInt(2) };
+            res = TDengine.StmtSetTbnameTags(stmt, "d1001", tags);
+            CheckStmtRes(res, "failed to bind table name and tags");
+
+            // 3. bind values
+            TAOS_MULTI_BIND[] values = new TAOS_MULTI_BIND[4] {
+                TaosMultiBind.MultiBindTimestamp(new long[2] { 1648432611249, 1648432611749}),
+                TaosMultiBind.MultiBindFloat(new float?[2] { 10.3f, 12.6f}),
+                TaosMultiBind.MultiBindInt(new int?[2] { 219, 218}),
+                TaosMultiBind.MultiBindFloat(new float?[2]{ 0.31f, 0.33f})
+            };
+            res = TDengine.StmtBindParamBatch(stmt, values);
+            CheckStmtRes(res, "failed to bind params");
+
+            // 4. add batch
+            res = TDengine.StmtAddBatch(stmt);
+            CheckStmtRes(res, "failed to add batch");
+
+            // 5. execute
+            res = TDengine.StmtExecute(stmt);
+            CheckStmtRes(res, "faild to execute");
+
+            // 6. free 
+            TaosBind.FreeTaosBind(tags);
+            TaosMultiBind.FreeTaosBind(values);
+            TDengine.Close(conn);
+            TDengine.Cleanup();
+        }
+
+        static IntPtr GetConnection()
+        {
+            string host = "localhost";
+            short port = 6030;
+            string username = "root";
+            string password = "taosdata";
+            string dbname = "";
+            var conn = TDengine.Connect(host, username, password, dbname, port);
+            if (conn == IntPtr.Zero)
+            {
+                Console.WriteLine("Connect to TDengine failed");
+                Environment.Exit(0);
+            }
+            else
+            {
+                Console.WriteLine("Connect to TDengine success");
+            }
+            return conn;
+        }
+
+
+
+        static void PrepareSTable()
+        {
+            IntPtr res = TDengine.Query(conn, "CREATE DATABASE power");
+            CheckResPtr(res, "failed to create database");
+            res = TDengine.Query(conn, "USE power");
+            CheckResPtr(res, "failed to change database");
+            res = TDengine.Query(conn, "CREATE STABLE power.meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) TAGS (location BINARY(64), groupId INT)");
+            CheckResPtr(res, "failed to create stable");
+        }
+
+        static void CheckStmtRes(int res, string errorMsg)
+        {
+            if (res != 0)
+            {
+                Console.WriteLine(errorMsg + ", " + TDengine.StmtErrorStr(stmt));
+                int code = TDengine.StmtClose(stmt);
+                if (code != 0)
+                {
+                    Console.WriteLine($"falied to close stmt, {code} reason: {TDengine.StmtErrorStr(stmt)} ");
+                }
+                ExitProgram();
+            }
+        }
+
+        static void CheckResPtr(IntPtr res, string errorMsg)
+        {
+            if (TDengine.ErrorNo(res) != 0)
+            {
+                Console.WriteLine(errorMsg + " since:" + TDengine.Error(res));
+                ExitProgram();
+            }
+        }
+
+        static void ExitProgram()
+        {
+            TDengine.Close(conn);
+            TDengine.Cleanup();
+            Environment.Exit(1);
+        }
+    }
+}

docs-examples/csharp/SubscribeDemo.cs

+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace csharp
+{
+    internal class SubscribeDemo
+    {
+    }
+}

docs-examples/csharp/asyncquery.csproj

+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net6.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <StartupObject>TDengineExample.AsyncQueryExample</StartupObject>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="TDengine.Connector" Version="1.0.6" />
+  </ItemGroup>
+
+</Project>

docs-examples/csharp/connect.csproj

+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net6.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <StartupObject>TDengineExample.ConnectExample</StartupObject>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="TDengine.Connector" Version="1.0.6" />
+  </ItemGroup>
+
+</Project>

docs-examples/csharp/influxdbline.csproj

+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net6.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <StartupObject>TDengineExample.InfluxDBLineExample</StartupObject>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="TDengine.Connector" Version="1.0.6" />
+  </ItemGroup>
+
+</Project>

docs-examples/csharp/optsjson.csproj

+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net6.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <StartupObject>TDengineExample.OptsJsonExample</StartupObject>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="TDengine.Connector" Version="1.0.6" />
+  </ItemGroup>
+
+</Project>

docs-examples/csharp/optstelnet.csproj

+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net6.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <StartupObject>TDengineExample.OptsTelnetExample</StartupObject>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="TDengine.Connector" Version="1.0.6" />
+  </ItemGroup>
+
+</Project>

docs-examples/csharp/query.csproj

+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net6.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <StartupObject>TDengineExample.QueryExample</StartupObject>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="TDengine.Connector" Version="1.0.6" />
+  </ItemGroup>
+
+</Project>

docs-examples/csharp/sqlinsert.csproj

+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net6.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <StartupObject>TDengineExample.SQLInsertExample</StartupObject>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="TDengine.Connector" Version="1.0.6" />
+  </ItemGroup>
+
+</Project>

docs-examples/csharp/stmtinsert.csproj

+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net6.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <StartupObject>TDengineExample.StmtInsertExample</StartupObject>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="TDengine.Connector" Version="1.0.6" />
+  </ItemGroup>
+
+</Project>

docs-examples/csharp/subscribe.csproj

+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net6.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+    <StartupObject>TDengineExample.SubscribeDemo</StartupObject>
+  </PropertyGroup>
+
+  <ItemGroup>
+    <PackageReference Include="TDengine.Connector" Version="1.0.6" />
+  </ItemGroup>
+
+</Project>

docs-examples/go/.gitignore

+.idea
+.vscode
+tmp/
\ No newline at end of file

docs-examples/go/connect/afconn/main.go

+package main
+
+import (
+	"fmt"
+
+	"github.com/taosdata/driver-go/v2/af"
+)
+
+func main() {
+	conn, err := af.Open("localhost", "root", "taosdata", "", 6030)
+	defer conn.Close()
+	if err != nil {
+		fmt.Println("failed to connect, err:", err)
+	} else {
+		fmt.Println("connected")
+	}
+}

docs-examples/go/connect/cgoexample/main.go

+package main
+
+import (
+	"database/sql"
+	"fmt"
+
+	_ "github.com/taosdata/driver-go/v2/taosSql"
+)
+
+func main() {
+	var taosDSN = "root:taosdata@tcp(localhost:6030)/"
+	taos, err := sql.Open("taosSql", taosDSN)
+	if err != nil {
+		fmt.Println("failed to connect TDengine, err:", err)
+		return
+	}
+	fmt.Println("Connected")
+	defer taos.Close()
+}
+
+// use
+// var taosDSN = "root:taosdata@tcp(localhost:6030)/dbName"
+// if you want to connect to a default database.

docs-examples/go/connect/restexample/main.go

+package main
+
+import (
+	"database/sql"
+	"fmt"
+
+	_ "github.com/taosdata/driver-go/v2/taosRestful"
+)
+
+func main() {
+	var taosDSN = "root:taosdata@http(localhost:6041)/"
+	taos, err := sql.Open("taosRestful", taosDSN)
+	if err != nil {
+		fmt.Println("failed to connect TDengine, err:", err)
+		return
+	}
+	fmt.Println("Connected")
+	defer taos.Close()
+}
+
+// use 
+// var taosDSN = "root:taosdata@http(localhost:6041)/dbName"
+// if you want to connect to a default database.

docs-examples/go/connect/wrapper/main.go

+package main
+
+import (
+	"fmt"
+
+	"github.com/taosdata/driver-go/v2/wrapper"
+)
+
+func main() {
+	conn, err := wrapper.TaosConnect("localhost", "root", "taosdata", "", 6030)
+	defer wrapper.TaosClose(conn)
+	if err != nil {
+		fmt.Println("fail to connect, err:", err)
+	} else {
+		fmt.Println("connected")
+	}
+}

docs-examples/go/go.mod

+module goexample
+
+go 1.17
+
+require github.com/taosdata/driver-go/v2 develop
+

docs-examples/go/insert/json/main.go

+package main
+
+import (
+	"fmt"
+
+	"github.com/taosdata/driver-go/v2/af"
+)
+
+func prepareDatabase(conn *af.Connector) {
+	_, err := conn.Exec("CREATE DATABASE test")
+	if err != nil {
+		panic(err)
+	}
+	_, err = conn.Exec("USE test")
+	if err != nil {
+		panic(err)
+	}
+}
+
+func main() {
+	conn, err := af.Open("localhost", "root", "taosdata", "", 6030)
+	if err != nil {
+		fmt.Println("fail to connect, err:", err)
+	}
+	defer conn.Close()
+	prepareDatabase(conn)
+
+	payload := `[{"metric": "meters.current", "timestamp": 1648432611249, "value": 10.3, "tags": {"location": "Beijing.Chaoyang", "groupid": 2}},
+				{"metric": "meters.voltage", "timestamp": 1648432611249, "value": 219, "tags": {"location": "Beijing.Haidian", "groupid": 1}},
+				{"metric": "meters.current", "timestamp": 1648432611250, "value": 12.6, "tags": {"location": "Beijing.Chaoyang", "groupid": 2}},
+				{"metric": "meters.voltage", "timestamp": 1648432611250, "value": 221, "tags": {"location": "Beijing.Haidian", "groupid": 1}}]`
+
+	err = conn.OpenTSDBInsertJsonPayload(payload)
+	if err != nil {
+		fmt.Println("insert error:", err)
+	}
+}

docs-examples/go/insert/line/main.go

+package main
+
+import (
+	"fmt"
+
+	"github.com/taosdata/driver-go/v2/af"
+)
+
+func prepareDatabase(conn *af.Connector) {
+	_, err := conn.Exec("CREATE DATABASE test")
+	if err != nil {
+		panic(err)
+	}
+	_, err = conn.Exec("USE test")
+	if err != nil {
+		panic(err)
+	}
+}
+
+func main() {
+	conn, err := af.Open("localhost", "root", "taosdata", "", 6030)
+	if err != nil {
+		fmt.Println("fail to connect, err:", err)
+	}
+	defer conn.Close()
+	prepareDatabase(conn)
+	var lines = []string{
+		"meters,location=Beijing.Haidian,groupid=2 current=11.8,voltage=221,phase=0.28 1648432611249",
+		"meters,location=Beijing.Haidian,groupid=2 current=13.4,voltage=223,phase=0.29 1648432611250",
+		"meters,location=Beijing.Haidian,groupid=3 current=10.8,voltage=223,phase=0.29 1648432611249",
+		"meters,location=Beijing.Haidian,groupid=3 current=11.3,voltage=221,phase=0.35 1648432611250",
+	}
+
+	err = conn.InfluxDBInsertLines(lines, "ms")
+	if err != nil {
+		fmt.Println("insert error:", err)
+	}
+}

docs-examples/go/insert/stmt/main.go

+package main
+
+import (
+	"fmt"
+	"time"
+
+	"github.com/taosdata/driver-go/v2/af"
+	"github.com/taosdata/driver-go/v2/af/param"
+	"github.com/taosdata/driver-go/v2/common"
+)
+
+func checkErr(err error, prompt string) {
+	if err != nil {
+		fmt.Printf("%s\n", prompt)
+		panic(err)
+	}
+}
+
+func prepareStable(conn *af.Connector) {
+	_, err := conn.Exec("CREATE DATABASE power")
+	checkErr(err, "failed to create database")
+	_, err = conn.Exec("CREATE STABLE power.meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) TAGS (location BINARY(64), groupId INT)")
+	checkErr(err, "failed to create stable")
+	_, err = conn.Exec("USE power")
+	checkErr(err, "failed to change database")
+}
+
+func main() {
+	conn, err := af.Open("localhost", "root", "taosdata", "", 6030)
+	checkErr(err, "fail to connect")
+	defer conn.Close()
+	prepareStable(conn)
+	// create stmt
+	stmt := conn.InsertStmt()
+	defer stmt.Close()
+	err = stmt.Prepare("INSERT INTO ? USING meters TAGS(?, ?) VALUES(?, ?, ?, ?)")
+	checkErr(err, "failed to create prepare statement")
+
+	// bind table name and tags
+	tagParams := param.NewParam(2).AddBinary([]byte("Beijing.Chaoyang")).AddInt(2)
+	err = stmt.SetTableNameWithTags("d1001", tagParams)
+	checkErr(err, "failed to execute SetTableNameWithTags")
+
+	// specify ColumnType
+	var bindType *param.ColumnType = param.NewColumnType(4).AddTimestamp().AddFloat().AddInt().AddFloat()
+
+	// bind values. note: can only bind one row each time.
+	valueParams := []*param.Param{
+		param.NewParam(1).AddTimestamp(time.Unix(1648432611, 249300000), common.PrecisionMilliSecond),
+		param.NewParam(1).AddFloat(10.3),
+		param.NewParam(1).AddInt(219),
+		param.NewParam(1).AddFloat(0.31),
+	}
+	err = stmt.BindParam(valueParams, bindType)
+	checkErr(err, "BindParam error")
+	err = stmt.AddBatch()
+	checkErr(err, "AddBatch error")
+
+	// bind one more row
+	valueParams = []*param.Param{
+		param.NewParam(1).AddTimestamp(time.Unix(1648432611, 749300000), common.PrecisionMilliSecond),
+		param.NewParam(1).AddFloat(12.6),
+		param.NewParam(1).AddInt(218),
+		param.NewParam(1).AddFloat(0.33),
+	}
+	err = stmt.BindParam(valueParams, bindType)
+	checkErr(err, "BindParam error")
+	err = stmt.AddBatch()
+	checkErr(err, "AddBatch error")
+	// execute
+	err = stmt.Execute()
+	checkErr(err, "Execute batch error")
+}

docs-examples/go/insert/telnet/main.go

+package main
+
+import (
+	"fmt"
+
+	"github.com/taosdata/driver-go/v2/af"
+)
+
+func prepareDatabase(conn *af.Connector) {
+	_, err := conn.Exec("CREATE DATABASE test")
+	if err != nil {
+		panic(err)
+	}
+	_, err = conn.Exec("USE test")
+	if err != nil {
+		panic(err)
+	}
+}
+
+func main() {
+	conn, err := af.Open("localhost", "root", "taosdata", "", 6030)
+	if err != nil {
+		fmt.Println("fail to connect, err:", err)
+	}
+	defer conn.Close()
+	prepareDatabase(conn)
+	var lines = []string{
+		"meters.current 1648432611249 10.3 location=Beijing.Chaoyang groupid=2",
+		"meters.current 1648432611250 12.6 location=Beijing.Chaoyang groupid=2",
+		"meters.current 1648432611249 10.8 location=Beijing.Haidian groupid=3",
+		"meters.current 1648432611250 11.3 location=Beijing.Haidian groupid=3",
+		"meters.voltage 1648432611249 219 location=Beijing.Chaoyang groupid=2",
+		"meters.voltage 1648432611250 218 location=Beijing.Chaoyang groupid=2",
+		"meters.voltage 1648432611249 221 location=Beijing.Haidian groupid=3",
+		"meters.voltage 1648432611250 217 location=Beijing.Haidian groupid=3",
+	}
+
+	err = conn.OpenTSDBInsertTelnetLines(lines)
+	if err != nil {
+		fmt.Println("insert error:", err)
+	}
+}

docs-examples/go/query/async/main.go

+package main
+
+import "fmt"
+
+func main() {
+	fmt.Println("hello world!")
+}

docs-examples/go/query/sync/main.go

+package main
+
+import (
+	"database/sql"
+	"fmt"
+	"time"
+
+	_ "github.com/taosdata/driver-go/v2/taosRestful"
+)
+
+func main() {
+	var taosDSN = "root:taosdata@http(localhost:6041)/power"
+	taos, err := sql.Open("taosRestful", taosDSN)
+	if err != nil {
+		fmt.Println("failed to connect TDengine, err:", err)
+		return
+	}
+	defer taos.Close()
+	rows, err := taos.Query("SELECT ts, current FROM meters LIMIT 2")
+	if err != nil {
+		fmt.Println("failed to select from table, err:", err)
+		return
+	}
+
+	defer rows.Close()
+	for rows.Next() {
+		var r struct {
+			ts      time.Time
+			current float32
+		}
+		err := rows.Scan(&r.ts, &r.current)
+		if err != nil {
+			fmt.Println("scan error:\n", err)
+			return
+		}
+		fmt.Println(r.ts, r.current)
+	}
+}

docs-examples/go/rest/opentsdbjson/main.go

+package main
+
+import (
+	"bytes"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"time"
+)
+
+type Tags struct {
+	Location string `json:"location"`
+	Groupid  int32  `json:"groupid"`
+}
+
+type Metric struct {
+	Metric    string `json:"metric"`
+	Timestamp int64  `json:"timestamp"`
+	Value     int32  `json:"value"`
+	Tags      Tags   `json:"tags"`
+}
+
+func main() {
+	client := http.Client{}
+	for i := 0; i < 10; i++ {
+		metric := Metric{"voltage", time.Now().UnixMilli(), 1, Tags{"A", 1}}
+		json, err := json.Marshal(metric)
+		if err != nil {
+			panic(err)
+		}
+		req, err := http.NewRequest("POST", "http://localhost:6041/opentsdb/v1/put/json/rest_go", bytes.NewBuffer(json))
+		if err != nil {
+			panic(err)
+		}
+		req.Header.Set("Content-Type", "application/json")
+		req.Header.Set("Authorization", "Basic cm9vdDp0YW9zZGF0YQ==")
+		resp, err := client.Do(req)
+		if err != nil {
+			panic(err)
+		}
+		fmt.Printf("%v\n", resp)
+		time.Sleep(time.Second)
+
+	}
+}

docs-examples/go/sub/main.go

+package main
+
+import (
+	"database/sql/driver"
+	"fmt"
+	"io"
+	"os"
+	"time"
+
+	taos "github.com/taosdata/driver-go/v2/af"
+)
+
+func main() {
+	db, err := taos.Open("", "", "", "log", 0)
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(1)
+	}
+	defer db.Close()
+	topic, err := db.Subscribe(false, "taoslogtail", "select ts, level, ipaddr, content from log", time.Second)
+	if err != nil {
+		fmt.Fprintln(os.Stderr, err)
+		os.Exit(2)
+	}
+	defer topic.Unsubscribe(true)
+	for {
+		func() {
+			rows, err := topic.Consume()
+			defer func() { rows.Close(); time.Sleep(time.Second) }()
+			if err != nil {
+				fmt.Println(err)
+				os.Exit(3)
+			}
+			for {
+				values := make([]driver.Value, 4)
+				err := rows.Next(values)
+				if err == io.EOF {
+					break
+				} else if err != nil {
+					fmt.Fprintln(os.Stderr, err)
+					os.Exit(4)
+				}
+				ts := values[0].(time.Time)
+				level := values[1].(int8)
+				ipaddr := values[2].(string)
+				content := values[3].(string)
+				fmt.Printf("%s %d %s %s\n", ts.Format(time.StampMilli), level, ipaddr, content)
+			}
+		}()
+	}
+}
+
+// 未完成

docs-examples/java/.gitignore

+.idea
+.vscode
\ No newline at end of file

docs-examples/java/pom.xml

+<?xml version="1.0" encoding="UTF-8"?>
+
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+
+  <groupId>com.taos</groupId>
+  <artifactId>javaexample</artifactId>
+  <version>1.0</version>
+
+  <name>JavaExample</name>
+
+  <properties>
+    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+    <maven.compiler.source>1.8</maven.compiler.source>
+    <maven.compiler.target>1.8</maven.compiler.target>
+  </properties>
+
+  <dependencies>
+<!--    ANCHOR: dep-->
+    <dependency>
+      <groupId>com.taosdata.jdbc</groupId>
+      <artifactId>taos-jdbcdriver</artifactId>
+      <version>2.0.38</version>
+    </dependency>
+<!--    ANCHOR_END: dep-->
+    <dependency>
+      <groupId>junit</groupId>
+      <artifactId>junit</artifactId>
+      <version>4.13.1</version>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+
+</project>

docs-examples/java/src/main/java/com/taos/example/JNIConnectExample.java

+package com.taos.example;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+import java.util.Properties;
+
+import com.taosdata.jdbc.TSDBDriver;
+
+public class JNIConnectExample {
+    public static void main(String[] args) throws SQLException {
+        String jdbcUrl = "jdbc:TAOS://localhost:6030?user=root&password=taosdata";
+        Properties connProps = new Properties();
+        connProps.setProperty(TSDBDriver.PROPERTY_KEY_CHARSET, "UTF-8");
+        connProps.setProperty(TSDBDriver.PROPERTY_KEY_LOCALE, "en_US.UTF-8");
+        connProps.setProperty(TSDBDriver.PROPERTY_KEY_TIME_ZONE, "UTC-8");
+        Connection conn = DriverManager.getConnection(jdbcUrl, connProps);
+        System.out.println("Connected");
+        conn.close();
+    }
+}
+
+// use
+// String jdbcUrl = "jdbc:TAOS://localhost:6030/dbName?user=root&password=taosdata";
+// if you want to connect to a default database.
\ No newline at end of file

docs-examples/java/src/main/java/com/taos/example/JSONProtocolExample.java

+package com.taos.example;
+
+import com.taosdata.jdbc.SchemalessWriter;
+import com.taosdata.jdbc.enums.SchemalessProtocolType;
+import com.taosdata.jdbc.enums.SchemalessTimestampType;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+import java.sql.Statement;
+
+public class JSONProtocolExample {
+    private static Connection getConnection() throws SQLException {
+        String jdbcUrl = "jdbc:TAOS://localhost:6030?user=root&password=taosdata";
+        return DriverManager.getConnection(jdbcUrl);
+    }
+
+    private static void createDatabase(Connection conn) throws SQLException {
+        try (Statement stmt = conn.createStatement()) {
+            stmt.execute("CREATE DATABASE IF NOT EXISTS test");
+            stmt.execute("USE test");
+        }
+    }
+
+    private static String getJSONData() {
+        return "[{\"metric\": \"meters.current\", \"timestamp\": 1648432611249, \"value\": 10.3, \"tags\": {\"location\": \"Beijing.Chaoyang\", \"groupid\": 2}}," +
+                " {\"metric\": \"meters.voltage\", \"timestamp\": 1648432611249, \"value\": 219, \"tags\": {\"location\": \"Beijing.Haidian\", \"groupid\": 1}}, " +
+                "{\"metric\": \"meters.current\", \"timestamp\": 1648432611250, \"value\": 12.6, \"tags\": {\"location\": \"Beijing.Chaoyang\", \"groupid\": 2}}," +
+                " {\"metric\": \"meters.voltage\", \"timestamp\": 1648432611250, \"value\": 221, \"tags\": {\"location\": \"Beijing.Haidian\", \"groupid\": 1}}]";
+    }
+
+    public static void main(String[] args) throws SQLException {
+        try (Connection conn = getConnection()) {
+            createDatabase(conn);
+            SchemalessWriter writer = new SchemalessWriter(conn);
+            String jsonData = getJSONData();
+            writer.write(jsonData, SchemalessProtocolType.JSON, SchemalessTimestampType.NOT_CONFIGURED);
+        }
+    }
+}

docs-examples/java/src/main/java/com/taos/example/LineProtocolExample.java

+package com.taos.example;
+
+import com.taosdata.jdbc.SchemalessWriter;
+import com.taosdata.jdbc.enums.SchemalessProtocolType;
+import com.taosdata.jdbc.enums.SchemalessTimestampType;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+import java.sql.Statement;
+
+public class LineProtocolExample {
+    // format: measurement,tag_set field_set timestamp
+    private static String[] lines = {
+            "meters,location=Beijing.Haidian,groupid=2 current=11.8,voltage=221,phase=0.28 1648432611249000", // micro
+                                                                                                              // seconds
+            "meters,location=Beijing.Haidian,groupid=2 current=13.4,voltage=223,phase=0.29 1648432611249500",
+            "meters,location=Beijing.Haidian,groupid=3 current=10.8,voltage=223,phase=0.29 1648432611249300",
+            "meters,location=Beijing.Haidian,groupid=3 current=11.3,voltage=221,phase=0.35 1648432611249800",
+    };
+
+    private static Connection getConnection() throws SQLException {
+        String jdbcUrl = "jdbc:TAOS://localhost:6030?user=root&password=taosdata";
+        return DriverManager.getConnection(jdbcUrl);
+    }
+
+    private static void createDatabase(Connection conn) throws SQLException {
+        try (Statement stmt = conn.createStatement()) {
+            // the default precision is ms (microsecond), but we use us(microsecond) here.
+            stmt.execute("CREATE DATABASE IF NOT EXISTS test PRECISION 'us'");
+            stmt.execute("USE test");
+        }
+    }
+
+    public static void main(String[] args) throws SQLException {
+        try (Connection conn = getConnection()) {
+            createDatabase(conn);
+            SchemalessWriter writer = new SchemalessWriter(conn);
+            writer.write(lines, SchemalessProtocolType.LINE, SchemalessTimestampType.MICRO_SECONDS);
+        }
+    }
+}

docs-examples/java/src/main/java/com/taos/example/RESTConnectExample.java

+package com.taos.example;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+
+public class RESTConnectExample {
+    // ANCHOR: main
+    public static void main(String[] args) throws SQLException {
+        String jdbcUrl = "jdbc:TAOS-RS://localhost:6041?user=root&password=taosdata";
+        Connection conn = DriverManager.getConnection(jdbcUrl);
+        System.out.println("Connected");
+        conn.close();
+    }
+    // ANCHOR_END: main
+}
\ No newline at end of file

docs-examples/java/src/main/java/com/taos/example/RestInsertExample.java

+package com.taos.example;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+import java.sql.Statement;
+import java.util.Arrays;
+import java.util.List;
+
+
+public class RestInsertExample {
+    private static Connection getConnection() throws SQLException {
+        String jdbcUrl = "jdbc:TAOS-RS://localhost:6041?user=root&password=taosdata";
+        return DriverManager.getConnection(jdbcUrl);
+    }
+
+    private static List<String> getRawData() {
+        return Arrays.asList(
+                "d1001,2018-10-03 14:38:05.000,10.30000,219,0.31000,Beijing.Chaoyang,2",
+                "d1001,2018-10-03 14:38:15.000,12.60000,218,0.33000,Beijing.Chaoyang,2",
+                "d1001,2018-10-03 14:38:16.800,12.30000,221,0.31000,Beijing.Chaoyang,2",
+                "d1002,2018-10-03 14:38:16.650,10.30000,218,0.25000,Beijing.Chaoyang,3",
+                "d1003,2018-10-03 14:38:05.500,11.80000,221,0.28000,Beijing.Haidian,2",
+                "d1003,2018-10-03 14:38:16.600,13.40000,223,0.29000,Beijing.Haidian,2",
+                "d1004,2018-10-03 14:38:05.000,10.80000,223,0.29000,Beijing.Haidian,3",
+                "d1004,2018-10-03 14:38:06.500,11.50000,221,0.35000,Beijing.Haidian,3"
+        );
+    }
+
+
+    /**
+     * The generated SQL is:
+     * INSERT INTO power.d1001 USING power.meters TAGS(Beijing.Chaoyang, 2) VALUES('2018-10-03 14:38:05.000',10.30000,219,0.31000)
+     * power.d1001 USING power.meters TAGS(Beijing.Chaoyang, 2) VALUES('2018-10-03 14:38:15.000',12.60000,218,0.33000)
+     * power.d1001 USING power.meters TAGS(Beijing.Chaoyang, 2) VALUES('2018-10-03 14:38:16.800',12.30000,221,0.31000)
+     * power.d1002 USING power.meters TAGS(Beijing.Chaoyang, 3) VALUES('2018-10-03 14:38:16.650',10.30000,218,0.25000)
+     * power.d1003 USING power.meters TAGS(Beijing.Haidian, 2) VALUES('2018-10-03 14:38:05.500',11.80000,221,0.28000)
+     * power.d1003 USING power.meters TAGS(Beijing.Haidian, 2) VALUES('2018-10-03 14:38:16.600',13.40000,223,0.29000)
+     * power.d1004 USING power.meters TAGS(Beijing.Haidian, 3) VALUES('2018-10-03 14:38:05.000',10.80000,223,0.29000)
+     * power.d1004 USING power.meters TAGS(Beijing.Haidian, 3) VALUES('2018-10-03 14:38:06.500',11.50000,221,0.35000)
+     */
+    private static String getSQL() {
+        StringBuilder sb = new StringBuilder("INSERT INTO ");
+        for (String line : getRawData()) {
+            String[] ps = line.split(",");
+            sb.append("power." + ps[0]).append(" USING power.meters TAGS(")
+                    .append(ps[5]).append(", ") // tag: location
+                    .append(ps[6]) // tag: groupId
+                    .append(") VALUES(")
+                    .append('\'').append(ps[1]).append('\'').append(",") // ts
+                    .append(ps[2]).append(",") // current
+                    .append(ps[3]).append(",") // voltage
+                    .append(ps[4]).append(") "); // phase
+        }
+        return sb.toString();
+    }
+
+    public static void insertData() throws SQLException {
+        try (Connection conn = getConnection()) {
+            try (Statement stmt = conn.createStatement()) {
+                stmt.execute("CREATE DATABASE power KEEP 3650");
+                stmt.execute("CREATE STABLE power.meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) " +
+                        "TAGS (location BINARY(64), groupId INT)");
+                String sql = getSQL();
+                int rowCount = stmt.executeUpdate(sql);
+                System.out.println("rowCount=" + rowCount); // rowCount=8
+            }
+        }
+    }
+
+    public static void main(String[] args) throws SQLException {
+        insertData();
+    }
+}

docs-examples/java/src/main/java/com/taos/example/RestQueryExample.java

+package com.taos.example;
+
+import java.sql.*;
+
+public class RestQueryExample {
+    private static Connection getConnection() throws SQLException {
+        String jdbcUrl = "jdbc:TAOS-RS://localhost:6041/power?user=root&password=taosdata";
+        return DriverManager.getConnection(jdbcUrl);
+    }
+
+    private static void printRow(ResultSet rs) throws SQLException {
+        ResultSetMetaData meta = rs.getMetaData();
+        for (int i = 1; i <= meta.getColumnCount(); i++) {
+            String value = rs.getString(i);
+            System.out.print(value);
+            System.out.print("\t");
+        }
+        System.out.println();
+    }
+
+    private static void printColName(ResultSet rs) throws SQLException {
+        ResultSetMetaData meta = rs.getMetaData();
+        for (int i = 1; i <= meta.getColumnCount(); i++) {
+            String colLabel = meta.getColumnLabel(i);
+            System.out.print(colLabel);
+            System.out.print("\t");
+        }
+        System.out.println();
+    }
+
+    private static void processResult(ResultSet rs) throws SQLException {
+        printColName(rs);
+        while (rs.next()) {
+            printRow(rs);
+        }
+    }
+
+    private static void queryData() throws SQLException {
+        try (Connection conn = getConnection()) {
+            try (Statement stmt = conn.createStatement()) {
+                ResultSet rs = stmt.executeQuery("SELECT AVG(voltage) FROM meters GROUP BY location");
+                processResult(rs);
+            }
+        }
+    }
+
+    public static void main(String[] args) throws SQLException {
+        queryData();
+    }
+}
+
+// possible output:
+// avg(voltage)	location
+// 222.0	Beijing.Haidian
+// 219.0	Beijing.Chaoyang

docs-examples/java/src/main/java/com/taos/example/StmtInsertExample.java

+package com.taos.example;
+
+import com.taosdata.jdbc.TSDBPreparedStatement;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+import java.sql.Statement;
+import java.time.LocalDateTime;
+import java.time.ZoneOffset;
+import java.time.format.DateTimeFormatter;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+public class StmtInsertExample {
+    private static ArrayList<Long> tsToLongArray(String ts) {
+        ArrayList<Long> result = new ArrayList<>();
+        DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss.SSS");
+        LocalDateTime localDateTime = LocalDateTime.parse(ts, formatter);
+        result.add(localDateTime.toInstant(ZoneOffset.of("+8")).toEpochMilli());
+        return result;
+    }
+
+    private static <T> ArrayList<T> toArray(T v) {
+        ArrayList<T> result = new ArrayList<>();
+        result.add(v);
+        return result;
+    }
+
+    private static List<String> getRawData() {
+        return Arrays.asList(
+                "d1001,2018-10-03 14:38:05.000,10.30000,219,0.31000,Beijing.Chaoyang,2",
+                "d1001,2018-10-03 14:38:15.000,12.60000,218,0.33000,Beijing.Chaoyang,2",
+                "d1001,2018-10-03 14:38:16.800,12.30000,221,0.31000,Beijing.Chaoyang,2",
+                "d1002,2018-10-03 14:38:16.650,10.30000,218,0.25000,Beijing.Chaoyang,3",
+                "d1003,2018-10-03 14:38:05.500,11.80000,221,0.28000,Beijing.Haidian,2",
+                "d1003,2018-10-03 14:38:16.600,13.40000,223,0.29000,Beijing.Haidian,2",
+                "d1004,2018-10-03 14:38:05.000,10.80000,223,0.29000,Beijing.Haidian,3",
+                "d1004,2018-10-03 14:38:06.500,11.50000,221,0.35000,Beijing.Haidian,3"
+        );
+    }
+
+    private static Connection getConnection() throws SQLException {
+        String jdbcUrl = "jdbc:TAOS://localhost:6030?user=root&password=taosdata";
+        return DriverManager.getConnection(jdbcUrl);
+    }
+
+    private static void createTable(Connection conn) throws SQLException {
+        try (Statement stmt = conn.createStatement()) {
+            stmt.execute("CREATE DATABASE power KEEP 3650");
+            stmt.executeUpdate("USE power");
+            stmt.execute("CREATE STABLE meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) " +
+                    "TAGS (location BINARY(64), groupId INT)");
+        }
+    }
+
+    private static void insertData() throws SQLException {
+        try (Connection conn = getConnection()) {
+            createTable(conn);
+            String psql = "INSERT INTO ? USING meters TAGS(?, ?) VALUES(?, ?, ?, ?)";
+            try (TSDBPreparedStatement pst = (TSDBPreparedStatement) conn.prepareStatement(psql)) {
+                for (String line : getRawData()) {
+                    String[] ps = line.split(",");
+                    // bind table name and tags
+                    pst.setTableName(ps[0]);
+                    pst.setTagString(0, ps[5]);
+                    pst.setTagInt(1, Integer.valueOf(ps[6]));
+                    // bind values
+                    pst.setTimestamp(0, tsToLongArray(ps[1])); //ps[1] looks like: 2018-10-03 14:38:05.000
+                    pst.setFloat(1, toArray(Float.valueOf(ps[2])));
+                    pst.setInt(2, toArray(Integer.valueOf(ps[3])));
+                    pst.setFloat(3, toArray(Float.valueOf(ps[4])));
+                    pst.columnDataAddBatch();
+                }
+                pst.columnDataExecuteBatch();
+            }
+        }
+    }
+
+    public static void main(String[] args) throws SQLException {
+        insertData();
+    }
+}

docs-examples/java/src/main/java/com/taos/example/SubscribeDemo.java

+package com.taos.example;
+
+import com.taosdata.jdbc.TSDBConnection;
+import com.taosdata.jdbc.TSDBDriver;
+import com.taosdata.jdbc.TSDBResultSet;
+import com.taosdata.jdbc.TSDBSubscribe;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.ResultSetMetaData;
+import java.sql.SQLException;
+import java.util.Properties;
+import java.util.concurrent.TimeUnit;
+
+public class SubscribeDemo {
+    private static final String topic = "topic-meter-current-bg-10";
+    private static final String sql = "select * from meters where current > 10";
+
+    public static void main(String[] args) {
+        Connection connection = null;
+        TSDBSubscribe subscribe = null;
+
+        try {
+            Class.forName("com.taosdata.jdbc.TSDBDriver");
+            Properties properties = new Properties();
+            properties.setProperty(TSDBDriver.PROPERTY_KEY_CHARSET, "UTF-8");
+            properties.setProperty(TSDBDriver.PROPERTY_KEY_TIME_ZONE, "UTC-8");
+            String jdbcUrl = "jdbc:TAOS://127.0.0.1:6030/power?user=root&password=taosdata";
+            connection = DriverManager.getConnection(jdbcUrl, properties);
+            // create subscribe
+            subscribe = ((TSDBConnection) connection).subscribe(topic, sql, true); 
+            int count = 0;
+            while (count < 10) {
+                // wait 1 second to avoid frequent calls to consume
+                TimeUnit.SECONDS.sleep(1); 
+                // consume
+                TSDBResultSet resultSet = subscribe.consume();
+                if (resultSet == null) {
+                    continue;
+                }
+                ResultSetMetaData metaData = resultSet.getMetaData();
+                while (resultSet.next()) {
+                    int columnCount = metaData.getColumnCount();
+                    for (int i = 1; i <= columnCount; i++) {
+                        System.out.print(metaData.getColumnLabel(i) + ": " + resultSet.getString(i) + "\t");
+                    }
+                    System.out.println();
+                    count++;
+                }
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            try {
+                if (null != subscribe)
+                    // close subscribe
+                    subscribe.close(true);
+                if (connection != null)
+                    connection.close();
+            } catch (SQLException throwable) {
+                throwable.printStackTrace();
+            }
+        }
+    }
+}
\ No newline at end of file

docs-examples/java/src/main/java/com/taos/example/TelnetLineProtocolExample.java

+package com.taos.example;
+
+import com.taosdata.jdbc.SchemalessWriter;
+import com.taosdata.jdbc.enums.SchemalessProtocolType;
+import com.taosdata.jdbc.enums.SchemalessTimestampType;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+import java.sql.Statement;
+
+public class TelnetLineProtocolExample {
+    // format: <metric> <timestamp> <value> <tagk_1>=<tagv_1>[ <tagk_n>=<tagv_n>]
+    private static String[] lines = { "meters.current 1648432611249 10.3 location=Beijing.Chaoyang groupid=2",
+            "meters.current 1648432611250 12.6 location=Beijing.Chaoyang groupid=2",
+            "meters.current 1648432611249 10.8 location=Beijing.Haidian groupid=3",
+            "meters.current 1648432611250 11.3 location=Beijing.Haidian groupid=3",
+            "meters.voltage 1648432611249 219 location=Beijing.Chaoyang groupid=2",
+            "meters.voltage 1648432611250 218 location=Beijing.Chaoyang groupid=2",
+            "meters.voltage 1648432611249 221 location=Beijing.Haidian groupid=3",
+            "meters.voltage 1648432611250 217 location=Beijing.Haidian groupid=3",
+    };
+
+    private static Connection getConnection() throws SQLException {
+        String jdbcUrl = "jdbc:TAOS://localhost:6030?user=root&password=taosdata";
+        return DriverManager.getConnection(jdbcUrl);
+    }
+
+    private static void createDatabase(Connection conn) throws SQLException {
+        try (Statement stmt = conn.createStatement()) {
+            // the default precision is ms (microsecond), but we use us(microsecond) here.
+            stmt.execute("CREATE DATABASE IF NOT EXISTS test precision 'us'");
+            stmt.execute("USE test");
+        }
+    }
+
+    public static void main(String[] args) throws SQLException {
+        try (Connection conn = getConnection()) {
+            createDatabase(conn);
+            SchemalessWriter writer = new SchemalessWriter(conn);
+            writer.write(lines, SchemalessProtocolType.TELNET, SchemalessTimestampType.NOT_CONFIGURED);
+        }
+    }
+
+}

docs-examples/java/src/main/java/com/taos/example/WSConnectExample.java

+package com.taos.example;
+
+import com.taosdata.jdbc.TSDBDriver;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.sql.SQLException;
+import java.util.Properties;
+
+public class WSConnectExample {
+    // ANCHOR: main
+    public static void main(String[] args) throws SQLException {
+        String jdbcUrl = "jdbc:TAOS-RS://localhost:6041?user=root&password=taosdata";
+        Properties connProps = new Properties();
+        connProps.setProperty(TSDBDriver.PROPERTY_KEY_BATCH_LOAD, "true");
+        Connection conn = DriverManager.getConnection(jdbcUrl, connProps);
+        System.out.println("Connected");
+        conn.close();
+    }
+    // ANCHOR_END: main
+}

docs-examples/java/src/test/java/com/taos/test/TestAll.java

+package com.taos.test;
+
+import com.taos.example.*;
+import org.junit.FixMethodOrder;
+import org.junit.Test;
+
+import java.sql.*;
+
+@FixMethodOrder
+public class TestAll {
+    private String[] args = new String[]{};
+
+    public void dropDB(String dbName) throws SQLException {
+        String jdbcUrl = "jdbc:TAOS://localhost:6030?user=root&password=taosdata";
+        try (Connection conn = DriverManager.getConnection(jdbcUrl)) {
+            try (Statement stmt = conn.createStatement()) {
+                stmt.execute("drop database if exists " + dbName);
+            }
+        }
+    }
+
+    public void insertData() throws SQLException {
+        String jdbcUrl = "jdbc:TAOS://localhost:6030?user=root&password=taosdata";
+        try (Connection conn = DriverManager.getConnection(jdbcUrl)) {
+            try (Statement stmt = conn.createStatement()) {
+                String sql = "INSERT INTO power.d1001 USING power.meters TAGS(Beijing.Chaoyang, 2) VALUES('2018-10-03 14:38:05.000',10.30000,219,0.31000)\n" +
+                        "                        power.d1001 USING power.meters TAGS(Beijing.Chaoyang, 2) VALUES('2018-10-03 15:38:15.000',12.60000,218,0.33000)\n" +
+                        "                        power.d1001 USING power.meters TAGS(Beijing.Chaoyang, 2) VALUES('2018-10-03 15:38:16.800',12.30000,221,0.31000)\n" +
+                        "                        power.d1002 USING power.meters TAGS(Beijing.Chaoyang, 3) VALUES('2018-10-03 15:38:16.650',10.30000,218,0.25000)\n" +
+                        "                        power.d1003 USING power.meters TAGS(Beijing.Haidian, 2) VALUES('2018-10-03 15:38:05.500',11.80000,221,0.28000)\n" +
+                        "                        power.d1003 USING power.meters TAGS(Beijing.Haidian, 2) VALUES('2018-10-03 15:38:16.600',13.40000,223,0.29000)\n" +
+                        "                        power.d1004 USING power.meters TAGS(Beijing.Haidian, 3) VALUES('2018-10-03 15:38:05.000',10.80000,223,0.29000)\n" +
+                        "                        power.d1004 USING power.meters TAGS(Beijing.Haidian, 3) VALUES('2018-10-03 15:38:06.000',10.80000,223,0.29000)\n" +
+                        "                        power.d1004 USING power.meters TAGS(Beijing.Haidian, 3) VALUES('2018-10-03 15:38:07.000',10.80000,223,0.29000)\n" +
+                        "                        power.d1004 USING power.meters TAGS(Beijing.Haidian, 3) VALUES('2018-10-03 15:38:08.500',11.50000,221,0.35000)";
+
+                stmt.execute(sql);
+            }
+        }
+    }
+
+    @Test
+    public void testJNIConnect() throws SQLException {
+        JNIConnectExample.main(args);
+    }
+
+    @Test
+    public void testRestConnect() throws SQLException {
+        RESTConnectExample.main(args);
+    }
+
+    @Test
+    public void testRestInsert() throws SQLException {
+        dropDB("power");
+        RestInsertExample.main(args);
+        RestQueryExample.main(args);
+    }
+
+    @Test
+    public void testStmtInsert() throws SQLException {
+        dropDB("power");
+        StmtInsertExample.main(args);
+    }
+
+    @Test
+    public void testSubscribe() {
+
+        Thread thread = new Thread(() -> {
+            try {
+                Thread.sleep(1000);
+                insertData();
+            } catch (SQLException e) {
+                e.printStackTrace();
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+            }
+        });
+        thread.start();
+        SubscribeDemo.main(args);
+    }
+
+    @Test
+    public void testSchemaless() throws SQLException {
+        LineProtocolExample.main(args);
+        TelnetLineProtocolExample.main(args);
+        // for json protocol, tags may be double type. but for telnet protocol tag must be nchar type.
+        // To avoid type mismatch, we delete database test.
+        dropDB("test");
+        JSONProtocolExample.main(args);
+    }
+}

docs-examples/node/.gitignore

+node_modules
+package-lock.json
+yarn-lock.json
\ No newline at end of file

docs-examples/node/nativeexample/async_query_example.js

+const taos = require("td2.0-connector");
+const conn = taos.connect({ host: "localhost", database: "power" });
+const cursor = conn.cursor();
+
+function queryExample() {
+  cursor
+    .query("SELECT ts, current FROM meters LIMIT 2")
+    .execute_a()
+    .then((result) => {
+      result.pretty();
+    });
+}
+
+try {
+  queryExample();
+} finally {
+  setTimeout(() => {
+    conn.close();
+  }, 2000);
+}
+// bug here: jira 14506

docs-examples/node/nativeexample/connect.js

+const taos = require("td2.0-connector");
+
+var conn = taos.connect({
+  host: "localhost",
+  port: 6030,
+  user: "root",
+  password: "taosdata",
+});
+conn.close();
+
+// run with: node connect.js
+// output:
+// Successfully connected to TDengine

docs-examples/node/nativeexample/influxdb_line_example.js

+const taos = require("td2.0-connector");
+
+const conn = taos.connect({
+  host: "localhost",
+});
+
+const cursor = conn.cursor();
+
+function createDatabase() {
+  cursor.execute("CREATE DATABASE test");
+  cursor.execute("USE test");
+}
+
+function insertData() {
+  const lines = [
+    "meters,location=Beijing.Haidian,groupid=2 current=11.8,voltage=221,phase=0.28 1648432611249",
+    "meters,location=Beijing.Haidian,groupid=2 current=13.4,voltage=223,phase=0.29 1648432611250",
+    "meters,location=Beijing.Haidian,groupid=3 current=10.8,voltage=223,phase=0.29 1648432611249",
+    "meters,location=Beijing.Haidian,groupid=3 current=11.3,voltage=221,phase=0.35 1648432611250",
+  ];
+  cursor.schemalessInsert(
+    lines,
+    taos.SCHEMALESS_PROTOCOL.TSDB_SML_LINE_PROTOCOL,
+    taos.SCHEMALESS_PRECISION.TSDB_SML_TIMESTAMP_MILLI_SECONDS
+  );
+}
+
+try {
+  createDatabase();
+  insertData();
+} finally {
+  cursor.close(); 
+  conn.close();
+}

docs-examples/node/nativeexample/insert_example.js

+const taos = require("td2.0-connector");
+
+const conn = taos.connect({
+  host: "localhost",
+});
+
+const cursor = conn.cursor();
+try {
+  cursor.execute("CREATE DATABASE power");
+  cursor.execute("USE power");
+  cursor.execute(
+    "CREATE STABLE meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) TAGS (location BINARY(64), groupId INT)"
+  );
+  var sql = `INSERT INTO power.d1001 USING power.meters TAGS(Beijing.Chaoyang, 2) VALUES ('2018-10-03 14:38:05.000', 10.30000, 219, 0.31000) ('2018-10-03 14:38:15.000', 12.60000, 218, 0.33000) ('2018-10-03 14:38:16.800', 12.30000, 221, 0.31000)
+power.d1002 USING power.meters TAGS(Beijing.Chaoyang, 3) VALUES ('2018-10-03 14:38:16.650', 10.30000, 218, 0.25000)
+power.d1003 USING power.meters TAGS(Beijing.Haidian, 2) VALUES ('2018-10-03 14:38:05.500', 11.80000, 221, 0.28000) ('2018-10-03 14:38:16.600', 13.40000, 223, 0.29000)
+power.d1004 USING power.meters TAGS(Beijing.Haidian, 3) VALUES ('2018-10-03 14:38:05.000', 10.80000, 223, 0.29000) ('2018-10-03 14:38:06.500', 11.50000, 221, 0.35000)`;
+  cursor.execute(sql);
+} finally {
+  cursor.close();
+  conn.close();
+}
+
+// run with: node insert_example.js
+// output:
+// Successfully connected to TDengine
+// Query OK, 0 row(s) affected (0.00509570s)
+// Query OK, 0 row(s) affected (0.00130880s)
+// Query OK, 0 row(s) affected (0.00467900s)
+// Query OK, 8 row(s) affected (0.04043550s)
+// Connection is closed

docs-examples/node/nativeexample/multi_bind_example.js

+const taos = require("td2.0-connector");
+
+const conn = taos.connect({
+  host: "localhost",
+});
+
+const cursor = conn.cursor();
+
+function prepareSTable() {
+  cursor.execute("CREATE DATABASE power");
+  cursor.execute("USE power");
+  cursor.execute(
+    "CREATE STABLE meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) TAGS (location BINARY(64), groupId INT)"
+  );
+}
+
+//ANCHOR: insertData
+function insertData() {
+  // init
+  cursor.stmtInit();
+  // prepare
+  cursor.stmtPrepare(
+    "INSERT INTO ? USING meters TAGS(?, ?) VALUES(?, ?, ?, ?)"
+  );
+
+  // bind table name and tags
+  let tagBind = new taos.TaosBind(2);
+  tagBind.bindBinary("Beijing.Chaoyang");
+  tagBind.bindInt(2);
+  cursor.stmtSetTbnameTags("d1001", tagBind.getBind());
+
+  // bind values
+  let valueBind = new taos.TaosMultiBindArr(4);
+  valueBind.multiBindTimestamp([1648432611249, 1648432611749]);
+  valueBind.multiBindFloat([10.3, 12.6]);
+  valueBind.multiBindInt([219, 218]);
+  valueBind.multiBindFloat([0.31, 0.33]);
+  cursor.stmtBindParamBatch(valueBind.getMultiBindArr());
+  cursor.stmtAddBatch();
+
+  // execute
+  cursor.stmtExecute();
+  cursor.stmtClose();
+}
+//ANCHOR_END: insertData
+
+try {
+  prepareSTable();
+  insertData();
+} finally {
+  cursor.close();
+  conn.close();
+}

docs-examples/node/nativeexample/opentsdb_json_example.js

+const taos = require("td2.0-connector");
+
+const conn = taos.connect({
+  host: "localhost",
+});
+
+const cursor = conn.cursor();
+
+function createDatabase() {
+  cursor.execute("CREATE DATABASE test");
+  cursor.execute("USE test");
+}
+
+function insertData() {
+  const lines = [
+    {
+      metric: "meters.current",
+      timestamp: 1648432611249,
+      value: 10.3,
+      tags: { location: "Beijing.Chaoyang", groupid: 2 },
+    },
+    {
+      metric: "meters.voltage",
+      timestamp: 1648432611249,
+      value: 219,
+      tags: { location: "Beijing.Haidian", groupid: 1 },
+    },
+    {
+      metric: "meters.current",
+      timestamp: 1648432611250,
+      value: 12.6,
+      tags: { location: "Beijing.Chaoyang", groupid: 2 },
+    },
+    {
+      metric: "meters.voltage",
+      timestamp: 1648432611250,
+      value: 221,
+      tags: { location: "Beijing.Haidian", groupid: 1 },
+    },
+  ];
+
+  cursor.schemalessInsert(
+    [JSON.stringify(lines)],
+    taos.SCHEMALESS_PROTOCOL.TSDB_SML_JSON_PROTOCOL,
+    taos.SCHEMALESS_PRECISION.TSDB_SML_TIMESTAMP_NOT_CONFIGURED
+  );
+}
+
+try {
+  createDatabase();
+  insertData();
+} finally {
+  cursor.close(); 
+  conn.close();
+}

docs-examples/node/nativeexample/opentsdb_telnet_example.js

+const taos = require("td2.0-connector");
+
+const conn = taos.connect({
+  host: "localhost",
+});
+
+const cursor = conn.cursor();
+
+function createDatabase() {
+  cursor.execute("CREATE DATABASE test");
+  cursor.execute("USE test");
+}
+
+function insertData() {
+  const lines = [
+    "meters.current 1648432611249 10.3 location=Beijing.Chaoyang groupid=2",
+    "meters.current 1648432611250 12.6 location=Beijing.Chaoyang groupid=2",
+    "meters.current 1648432611249 10.8 location=Beijing.Haidian groupid=3",
+    "meters.current 1648432611250 11.3 location=Beijing.Haidian groupid=3",
+    "meters.voltage 1648432611249 219 location=Beijing.Chaoyang groupid=2",
+    "meters.voltage 1648432611250 218 location=Beijing.Chaoyang groupid=2",
+    "meters.voltage 1648432611249 221 location=Beijing.Haidian groupid=3",
+    "meters.voltage 1648432611250 217 location=Beijing.Haidian groupid=3",
+  ];
+  cursor.schemalessInsert(
+    lines,
+    taos.SCHEMALESS_PROTOCOL.TSDB_SML_TELNET_PROTOCOL,
+    taos.SCHEMALESS_PRECISION.TSDB_SML_TIMESTAMP_NOT_CONFIGURED
+  );
+}
+
+try {
+  createDatabase();
+  insertData();
+} finally {
+  cursor.close();
+  conn.close();
+}

docs-examples/node/nativeexample/param_bind_example.js

+const taos = require("td2.0-connector");
+
+const conn = taos.connect({
+  host: "localhost",
+});
+
+const cursor = conn.cursor();
+
+function prepareSTable() {
+  cursor.execute("CREATE DATABASE power");
+  cursor.execute("USE power");
+  cursor.execute(
+    "CREATE STABLE meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) TAGS (location BINARY(64), groupId INT)"
+  );
+}
+
+function insertData() {
+  // init
+  cursor.stmtInit();
+  // prepare
+  cursor.stmtPrepare(
+    "INSERT INTO ? USING meters TAGS(?, ?) VALUES(?, ?, ?, ?)"
+  );
+
+  // bind table name and tags
+  let tagBind = new taos.TaosBind(2);
+  tagBind.bindBinary("Beijing.Chaoyang");
+  tagBind.bindInt(2);
+  cursor.stmtSetTbnameTags("d1001", tagBind.getBind());
+
+  // bind values
+  let rows = [
+    [1648432611249, 10.3, 219, 0.31],
+    [1648432611749, 12.6, 218, 0.33],
+  ];
+  for (let row of rows) {
+    let valueBind = new taos.TaosBind(4);
+    valueBind.bindTimestamp(row[0]);
+    valueBind.bindFloat(row[1]);
+    valueBind.bindInt(row[2]);
+    valueBind.bindFloat(row[3]);
+    cursor.stmtBindParam(valueBind.getBind());
+    cursor.stmtAddBatch();
+  }
+
+  // execute
+  cursor.stmtExecute();
+  cursor.stmtClose();
+}
+
+try {
+  prepareSTable();
+  insertData();
+} finally {
+  cursor.close();
+  conn.close();
+}

docs-examples/node/nativeexample/query_example.js

+const taos = require("td2.0-connector");
+
+const conn = taos.connect({ host: "localhost", database: "power" });
+const cursor = conn.cursor();
+const query = cursor.query("SELECT ts, current FROM meters LIMIT 2");
+query.execute().then(function (result) {
+  result.pretty();
+});
+
+// output:
+// Successfully connected to TDengine
+// Query OK, 2 row(s) in set (0.00317767s)
+
+//            ts             |         current          |
+// =======================================================
+// 2018-10-03 14:38:05.000   | 10.3                     |
+// 2018-10-03 14:38:15.000   | 12.6                     |

docs-examples/node/nativeexample/subscribe_demo.js

+const taos = require("td2.0-connector");
+
+const conn = taos.connect({ host: "localhost", database: "power" });
+// 未完成
\ No newline at end of file

docs-examples/node/package.json

+{
+  "name": "examples",
+  "version": "1.0.0",
+  "main": "index.js",
+  "license": "MIT",
+  "dependencies": {
+    "td2.0-connector": "^2.0.12",
+    "td2.0-rest-connector": "^1.0.0"
+  }
+}

docs-examples/node/restexample/connect.js

+const { options, connect } = require("td2.0-rest-connector");
+
+async function test() {
+  options.path = "/rest/sqlt";
+  options.host = "localhost";
+  let conn = connect(options);
+  let cursor = conn.cursor();
+  try {
+    let res = await cursor.query("SELECT server_version()");
+    res.toString();
+  } catch (err) {
+    console.log(err);
+  }
+}
+test();
+
+// output:
+// server_version() |
+// ===================
+// 2.4.0.12         |

docs-examples/php/connect.php

+<?php
+
+use TDengine\Connection;
+use TDengine\Exception\TDengineException;
+
+try {
+    // 实例化
+    $host = 'localhost';
+    $port = 6030;
+    $username = 'root';
+    $password = 'taosdata';
+    $dbname = null;
+    $connection = new Connection($host, $port, $username, $password, $dbname);
+
+    // 连接
+    $connection->connect();
+} catch (TDengineException $e) {
+    // 连接失败捕获异常
+    throw $e;
+}

docs-examples/php/insert.php

+<?php
+
+use TDengine\Connection;
+use TDengine\Exception\TDengineException;
+
+try {
+    // 实例化
+    $host = 'localhost';
+    $port = 6030;
+    $username = 'root';
+    $password = 'taosdata';
+    $dbname = 'power';
+    $connection = new Connection($host, $port, $username, $password, $dbname);
+
+    // 连接
+    $connection->connect();
+
+    // 插入
+    $connection->query('CREATE DATABASE if not exists power');
+    $connection->query('CREATE STABLE if not exists meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) TAGS (location BINARY(64), groupId INT)');
+    $resource = $connection->query(<<<'SQL'
+    INSERT INTO power.d1001 USING power.meters TAGS(Beijing.Chaoyang, 2) VALUES ('2018-10-03 14:38:05.000', 10.30000, 219, 0.31000) ('2018-10-03 14:38:15.000', 12.60000, 218, 0.33000) ('2018-10-03 14:38:16.800', 12.30000, 221, 0.31000)
+    power.d1002 USING power.meters TAGS(Beijing.Chaoyang, 3) VALUES ('2018-10-03 14:38:16.650', 10.30000, 218, 0.25000)
+    power.d1003 USING power.meters TAGS(Beijing.Haidian, 2) VALUES ('2018-10-03 14:38:05.500', 11.80000, 221, 0.28000) ('2018-10-03 14:38:16.600', 13.40000, 223, 0.29000)
+    power.d1004 USING power.meters TAGS(Beijing.Haidian, 3) VALUES ('2018-10-03 14:38:05.000', 10.80000, 223, 0.29000) ('2018-10-03 14:38:06.500', 11.50000, 221, 0.35000)
+    SQL);
+
+    // 影响行数
+    var_dump($resource->affectedRows());
+} catch (TDengineException $e) {
+    // 捕获异常
+    throw $e;
+}

docs-examples/php/insert_stmt.php

+<?php
+
+use TDengine\Connection;
+use TDengine\Exception\TDengineException;
+
+try {
+    // 实例化
+    $host = 'localhost';
+    $port = 6030;
+    $username = 'root';
+    $password = 'taosdata';
+    $dbname = 'power';
+    $connection = new Connection($host, $port, $username, $password, $dbname);
+
+    // 连接
+    $connection->connect();
+
+    // 插入
+    $connection->query('CREATE DATABASE if not exists power');
+    $connection->query('CREATE STABLE if not exists meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) TAGS (location BINARY(64), groupId INT)');
+    $stmt = $connection->prepare('INSERT INTO ? USING meters TAGS(?, ?) VALUES(?, ?, ?, ?)');
+
+    // 设置表名和标签
+    $stmt->setTableNameTags('d1001', [
+        // 支持格式同参数绑定
+        [TDengine\TSDB_DATA_TYPE_BINARY, 'Beijing.Chaoyang'],
+        [TDengine\TSDB_DATA_TYPE_INT, 2],
+    ]);
+
+    $stmt->bindParams([
+        [TDengine\TSDB_DATA_TYPE_TIMESTAMP, 1648432611249],
+        [TDengine\TSDB_DATA_TYPE_FLOAT, 10.3],
+        [TDengine\TSDB_DATA_TYPE_INT, 219],
+        [TDengine\TSDB_DATA_TYPE_FLOAT, 0.31],
+    ]);
+    $stmt->bindParams([
+        [TDengine\TSDB_DATA_TYPE_TIMESTAMP, 1648432611749],
+        [TDengine\TSDB_DATA_TYPE_FLOAT, 12.6],
+        [TDengine\TSDB_DATA_TYPE_INT, 218],
+        [TDengine\TSDB_DATA_TYPE_FLOAT, 0.33],
+    ]);
+    $resource = $stmt->execute();
+
+    // 影响行数
+    var_dump($resource->affectedRows());
+} catch (TDengineException $e) {
+    // 捕获异常
+    throw $e;
+}

docs-examples/php/query.php

+<?php
+
+use TDengine\Connection;
+use TDengine\Exception\TDengineException;
+
+try {
+    // 实例化
+    $host = 'localhost';
+    $port = 6030;
+    $username = 'root';
+    $password = 'taosdata';
+    $dbname = 'power';
+    $connection = new Connection($host, $port, $username, $password, $dbname);
+
+    // 连接
+    $connection->connect();
+
+    $resource = $connection->query('SELECT ts, current FROM meters LIMIT 2');
+    var_dump($resource->fetch());
+} catch (TDengineException $e) {
+    // 捕获异常
+    throw $e;
+}

docs-examples/python/.gitignore

+.idea
\ No newline at end of file

docs-examples/python/async_query_example.py

+import time
+from ctypes import *
+
+from taos import *
+
+
+def fetch_callback(p_param, p_result, num_of_rows):
+    print("fetched ", num_of_rows, "rows")
+    p = cast(p_param, POINTER(Counter))
+    result = TaosResult(p_result)
+
+    if num_of_rows == 0:
+        print("fetching completed")
+        p.contents.done = True
+        result.close()
+        return
+    if num_of_rows < 0:
+        p.contents.done = True
+        result.check_error(num_of_rows)
+        result.close()
+        return None
+
+    for row in result.rows_iter(num_of_rows):
+        print(row)
+    p.contents.count += result.row_count
+    result.fetch_rows_a(fetch_callback, p_param)
+
+
+def query_callback(p_param, p_result, code):
+    if p_result is None:
+        return
+    result = TaosResult(p_result)
+    if code == 0:
+        result.fetch_rows_a(fetch_callback, p_param)
+    result.check_error(code)
+
+
+class Counter(Structure):
+    _fields_ = [("count", c_int), ("done", c_bool)]
+
+    def __str__(self):
+        return "{ count: %d, done: %s }" % (self.count, self.done)
+
+
+def test_query(conn):
+    counter = Counter(count=0)
+    conn.query_a("select ts, current, voltage from power.meters", query_callback, byref(counter))
+
+    while not counter.done:
+        print(counter)
+        time.sleep(1)
+    print(counter)
+    conn.close()
+
+
+if __name__ == "__main__":
+    test_query(connect())
+
+# possible output:
+# { count: 0, done: False }
+# fetched  8 rows
+# 1538548685000 10.300000 219
+# 1538548695000 12.600000 218
+# 1538548696800 12.300000 221
+# 1538548696650 10.300000 218
+# 1538548685500 11.800000 221
+# 1538548696600 13.400000 223
+# 1538548685500 10.800000 223
+# 1538548686500 11.500000 221
+# fetched  0 rows
+# fetching completed
+# { count: 8, done: True }

docs-examples/python/bind_param_example.py

+import taos
+from datetime import datetime
+
+# note: lines have already been sorted by table name
+lines = [('d1001', '2018-10-03 14:38:05.000', 10.30000, 219, 0.31000, 'Beijing.Chaoyang', 2),
+         ('d1001', '2018-10-03 14:38:15.000', 12.60000, 218, 0.33000, 'Beijing.Chaoyang', 2),
+         ('d1001', '2018-10-03 14:38:16.800', 12.30000, 221, 0.31000, 'Beijing.Chaoyang', 2),
+         ('d1002', '2018-10-03 14:38:16.650', 10.30000, 218, 0.25000, 'Beijing.Chaoyang', 3),
+         ('d1003', '2018-10-03 14:38:05.500', 11.80000, 221, 0.28000, 'Beijing.Haidian', 2),
+         ('d1003', '2018-10-03 14:38:16.600', 13.40000, 223, 0.29000, 'Beijing.Haidian', 2),
+         ('d1004', '2018-10-03 14:38:05.000', 10.80000, 223, 0.29000, 'Beijing.Haidian', 3),
+         ('d1004', '2018-10-03 14:38:06.500', 11.50000, 221, 0.35000, 'Beijing.Haidian', 3)]
+
+
+def get_ts(ts: str):
+    dt = datetime.strptime(ts, '%Y-%m-%d %H:%M:%S.%f')
+    return int(dt.timestamp() * 1000)
+
+
+def create_stable():
+    conn = taos.connect()
+    try:
+        conn.execute("CREATE DATABASE power")
+        conn.execute("CREATE STABLE power.meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) "
+                     "TAGS (location BINARY(64), groupId INT)")
+    finally:
+        conn.close()
+
+
+def bind_row_by_row(stmt: taos.TaosStmt):
+    tb_name = None
+    for row in lines:
+        if tb_name != row[0]:
+            tb_name = row[0]
+            tags: taos.TaosBind = taos.new_bind_params(2)  # 2 is count of tags
+            tags[0].binary(row[5])  # location
+            tags[1].int(row[6])  # groupId
+            stmt.set_tbname_tags(tb_name, tags)
+        values: taos.TaosBind = taos.new_bind_params(4)  # 4 is count of columns
+        values[0].timestamp(get_ts(row[1]))
+        values[1].float(row[2])
+        values[2].int(row[3])
+        values[3].float(row[4])
+        stmt.bind_param(values)
+
+
+def insert_data():
+    conn = taos.connect(database="power")
+    try:
+        stmt = conn.statement("INSERT INTO ? USING meters TAGS(?, ?) VALUES(?, ?, ?, ?)")
+        bind_row_by_row(stmt)
+        stmt.execute()
+        stmt.close()
+    finally:
+        conn.close()
+
+
+if __name__ == '__main__':
+    create_stable()
+    insert_data()

docs-examples/python/conn_native_pandas.py

+import pandas
+from sqlalchemy import create_engine
+
+engine = create_engine("taos://root:taosdata@localhost:6030/power")
+df = pandas.read_sql("SELECT * FROM meters", engine)
+
+# print index
+print(df.index)
+# print data type  of element in ts column
+print(type(df.ts[0]))
+print(df.head(3))
+
+# output:
+# RangeIndex(start=0, stop=8, step=1)
+# <class 'pandas._libs.tslibs.timestamps.Timestamp'>
+#                        ts  current  voltage  phase          location  groupid
+# 0 2018-10-03 14:38:05.000     10.3      219   0.31  beijing.chaoyang        2
+# 1 2018-10-03 14:38:15.000     12.6      218   0.33  beijing.chaoyang        2
+# 2 2018-10-03 14:38:16.800     12.3      221   0.31  beijing.chaoyang        2

docs-examples/python/conn_rest_pandas.py

+import pandas
+from sqlalchemy import create_engine
+
+engine = create_engine("taosrest://root:taosdata@localhost:6041")
+df: pandas.DataFrame = pandas.read_sql("SELECT * FROM power.meters", engine)
+
+# print index
+print(df.index)
+# print data type  of element in ts column
+print(type(df.ts[0]))
+print(df.head(3))
+
+# output:
+# <class 'datetime.datetime'>
+# RangeIndex(start=0, stop=8, step=1)
+#                                  ts  current  ...          location  groupid
+# 0         2018-10-03 14:38:05+08:00     10.3  ...  beijing.chaoyang        2
+# 1         2018-10-03 14:38:15+08:00     12.6  ...  beijing.chaoyang        2
+# 2  2018-10-03 14:38:16.800000+08:00     12.3  ...  beijing.chaoyang        2

docs-examples/python/connect_example.py

+import taos
+
+
+def test_connection():
+    # all parameters are optional.
+    # if database is specified,
+    # then it must exist.
+    conn = taos.connect(host="localhost",
+                        port=6030,
+                        user="root",
+                        password="taosdata",
+                        database="log")
+    print('client info:', conn.client_info)
+    print('server info:', conn.server_info)
+    conn.close()
+
+
+if __name__ == "__main__":
+    test_connection()

docs-examples/python/connect_native_reference.py

+import taos
+
+conn: taos.TaosConnection = taos.connect(host="localhost",
+                                         user="root",
+                                         password="taosdata",
+                                         database="test",
+                                         port=6030,
+                                         config="/etc/taos",  # for windows the default value is C:\TDengine\cfg
+                                         timezone="Asia/Shanghai")  # default your host's timezone
+
+server_version = conn.server_info
+print("server_version", server_version)
+client_version = conn.client_info
+print("client_version", client_version)  # 2.4.0.16
+
+conn.close()
+
+# possible output:
+# 2.4.0.16
+# 2.4.0.16

docs-examples/python/connect_rest_examples.py

+# ANCHOR: connect
+from taosrest import connect, TaosRestConnection, TaosRestCursor
+
+conn: TaosRestConnection = connect(host="localhost",
+                                   user="root",
+                                   password="taosdata",
+                                   port=6041,
+                                   timeout=30)
+
+# ANCHOR_END: connect
+# ANCHOR: basic
+# create STable
+cursor: TaosRestCursor = conn.cursor()
+cursor.execute("DROP DATABASE IF EXISTS power")
+cursor.execute("CREATE DATABASE power")
+cursor.execute("CREATE STABLE power.meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) TAGS (location BINARY(64), groupId INT)")
+
+# insert data
+cursor.execute("""INSERT INTO power.d1001 USING power.meters TAGS(Beijing.Chaoyang, 2) VALUES ('2018-10-03 14:38:05.000', 10.30000, 219, 0.31000) ('2018-10-03 14:38:15.000', 12.60000, 218, 0.33000) ('2018-10-03 14:38:16.800', 12.30000, 221, 0.31000)
+    power.d1002 USING power.meters TAGS(Beijing.Chaoyang, 3) VALUES ('2018-10-03 14:38:16.650', 10.30000, 218, 0.25000)
+    power.d1003 USING power.meters TAGS(Beijing.Haidian, 2) VALUES ('2018-10-03 14:38:05.500', 11.80000, 221, 0.28000) ('2018-10-03 14:38:16.600', 13.40000, 223, 0.29000)
+    power.d1004 USING power.meters TAGS(Beijing.Haidian, 3) VALUES ('2018-10-03 14:38:05.000', 10.80000, 223, 0.29000) ('2018-10-03 14:38:06.500', 11.50000, 221, 0.35000)""")
+print("inserted row count:", cursor.rowcount)
+
+# query data
+cursor.execute("SELECT * FROM power.meters LIMIT 3")
+# get total rows
+print("queried row count:", cursor.rowcount)
+# get column names from cursor
+column_names = [meta[0] for meta in cursor.description]
+# get rows
+data: list[tuple] = cursor.fetchall()
+print(column_names)
+for row in data:
+    print(row)
+
+# output:
+# inserted row count: 8
+# queried row count: 3
+# ['ts', 'current', 'voltage', 'phase', 'location', 'groupid']
+# [datetime.datetime(2018, 10, 3, 14, 38, 5, tzinfo=datetime.timezone(datetime.timedelta(seconds=28800), '+08:00')), 10.3, 219, 0.31, 'beijing.chaoyang', 2]
+# [datetime.datetime(2018, 10, 3, 14, 38, 15, tzinfo=datetime.timezone(datetime.timedelta(seconds=28800), '+08:00')), 12.6, 218, 0.33, 'beijing.chaoyang', 2]
+# [datetime.datetime(2018, 10, 3, 14, 38, 16, 800000, tzinfo=datetime.timezone(datetime.timedelta(seconds=28800), '+08:00')), 12.3, 221, 0.31, 'beijing.chaoyang', 2]
+
+# ANCHOR_END: basic

docs-examples/python/connection_usage_native_reference.py

+import taos
+
+# ANCHOR: insert
+conn = taos.connect()
+# Execute a sql, ignore the result set, just get affected rows. It's useful for DDL and DML statement.
+conn.execute("DROP DATABASE IF EXISTS test")
+conn.execute("CREATE DATABASE test")
+# change database. same as execute "USE db"
+conn.select_db("test")
+conn.execute("CREATE STABLE weather(ts TIMESTAMP, temperature FLOAT) TAGS (location INT)")
+affected_row: int = conn.execute("INSERT INTO t1 USING weather TAGS(1) VALUES (now, 23.5) (now+1m, 23.5) (now+2m 24.4)")
+print("affected_row", affected_row)
+# output:
+# affected_row 3
+# ANCHOR_END: insert
+
+# ANCHOR: query
+# Execute a sql and get its result set. It's useful for SELECT statement
+result: taos.TaosResult = conn.query("SELECT * from weather")
+
+# Get fields from result
+fields: taos.field.TaosFields = result.fields
+for field in fields:
+    print(field)  # {name: ts, type: 9, bytes: 8}
+
+# output:
+# {name: ts, type: 9, bytes: 8}
+# {name: temperature, type: 6, bytes: 4}
+# {name: location, type: 4, bytes: 4}
+
+# Get data from result as list of tuple
+data = result.fetch_all()
+print(data)
+# output:
+# [(datetime.datetime(2022, 4, 27, 9, 4, 25, 367000), 23.5, 1), (datetime.datetime(2022, 4, 27, 9, 5, 25, 367000), 23.5, 1), (datetime.datetime(2022, 4, 27, 9, 6, 25, 367000), 24.399999618530273, 1)]
+
+# Or get data from result as a list of dict
+# map_data = result.fetch_all_into_dict()
+# print(map_data)
+# output:
+# [{'ts': datetime.datetime(2022, 4, 27, 9, 1, 15, 343000), 'temperature': 23.5, 'location': 1}, {'ts': datetime.datetime(2022, 4, 27, 9, 2, 15, 343000), 'temperature': 23.5, 'location': 1}, {'ts': datetime.datetime(2022, 4, 27, 9, 3, 15, 343000), 'temperature': 24.399999618530273, 'location': 1}]
+# ANCHOR_END: query
+
+
+conn.close()

docs-examples/python/cursor_usage_native_reference.py

+import taos
+
+conn = taos.connect()
+cursor = conn.cursor()
+
+cursor.execute("DROP DATABASE IF EXISTS test")
+cursor.execute("CREATE DATABASE test")
+cursor.execute("USE test")
+cursor.execute("CREATE STABLE weather(ts TIMESTAMP, temperature FLOAT) TAGS (location INT)")
+
+for i in range(1000):
+    location = str(i % 10)
+    tb = "t" + location
+    cursor.execute(f"INSERT INTO {tb} USING weather TAGS({location}) VALUES (now+{i}a, 23.5) (now+{i + 1}a, 23.5)")
+
+cursor.execute("SELECT count(*) FROM weather")
+data = cursor.fetchall()
+print("count:", data[0][0])
+cursor.execute("SELECT tbname, * FROM weather LIMIT 2")
+col_names = [meta[0] for meta in cursor.description]
+print(col_names)
+rows = cursor.fetchall()
+print(rows)
+
+cursor.close()
+conn.close()
+
+# output:
+# count: 2000
+# ['tbname', 'ts', 'temperature', 'location']
+# row_count: -1
+# [('t0', datetime.datetime(2022, 4, 27, 14, 54, 24, 392000), 23.5, 0), ('t0', datetime.datetime(2022, 4, 27, 14, 54, 24, 393000), 23.5, 0)]

docs-examples/python/handle_exception.py

+import taos
+
+try:
+    conn = taos.connect()
+    conn.execute("CREATE TABLE 123")  # wrong sql
+except taos.Error as e:
+    print(e)
+    print("exception class: ", e.__class__.__name__)
+    print("error number:", e.errno)
+    print("error message:", e.msg)
+except BaseException as other:
+    print("exception occur")
+    print(other)
+
+# output:
+# [0x0216]: syntax error near 'Incomplete SQL statement'
+# exception class:  ProgrammingError
+# error number: -2147483114
+# error message: syntax error near 'Incomplete SQL statement'

docs-examples/python/json_protocol_example.py

+import json
+
+import taos
+from taos import SmlProtocol, SmlPrecision
+
+lines = [{"metric": "meters.current", "timestamp": 1648432611249, "value": 10.3, "tags": {"location": "Beijing.Chaoyang", "groupid": 2}},
+         {"metric": "meters.voltage", "timestamp": 1648432611249, "value": 219,
+             "tags": {"location": "Beijing.Haidian", "groupid": 1}},
+         {"metric": "meters.current", "timestamp": 1648432611250, "value": 12.6,
+             "tags": {"location": "Beijing.Chaoyang", "groupid": 2}},
+         {"metric": "meters.voltage", "timestamp": 1648432611250, "value": 221, "tags": {"location": "Beijing.Haidian", "groupid": 1}}]
+
+
+def get_connection():
+    return taos.connect()
+
+
+def create_database(conn):
+    conn.execute("CREATE DATABASE test")
+    conn.execute("USE test")
+
+
+def insert_lines(conn):
+    global lines
+    lines = json.dumps(lines)
+    # note: the first parameter must be a list with only one element.
+    affected_rows = conn.schemaless_insert(
+        [lines], SmlProtocol.JSON_PROTOCOL, SmlPrecision.NOT_CONFIGURED)
+    print(affected_rows)  # 4
+
+
+if __name__ == '__main__':
+    connection = get_connection()
+    try:
+        create_database(connection)
+        insert_lines(connection)
+    finally:
+        connection.close()

docs-examples/python/line_protocol_example.py

+import taos
+from taos import SmlProtocol, SmlPrecision
+
+lines = ["meters,location=Beijing.Haidian,groupid=2 current=11.8,voltage=221,phase=0.28 1648432611249000",
+         "meters,location=Beijing.Haidian,groupid=2 current=13.4,voltage=223,phase=0.29 1648432611249500",
+         "meters,location=Beijing.Haidian,groupid=3 current=10.8,voltage=223,phase=0.29 1648432611249300",
+         "meters,location=Beijing.Haidian,groupid=3 current=11.3,voltage=221,phase=0.35 1648432611249800",
+         ]
+
+
+def get_connection():
+    # create connection use firstEP in taos.cfg.
+    return taos.connect()
+
+
+def create_database(conn):
+    # the default precision is ms (microsecond), but we use us(microsecond) here.
+    conn.execute("CREATE DATABASE test precision 'us'")
+    conn.execute("USE test")
+
+
+def insert_lines(conn):
+    affected_rows = conn.schemaless_insert(
+        lines, SmlProtocol.LINE_PROTOCOL, SmlPrecision.MICRO_SECONDS)
+    print(affected_rows)  # 8
+
+
+if __name__ == '__main__':
+    connection = get_connection()
+    try:
+        create_database(connection)
+        insert_lines(connection)
+    finally:
+        connection.close()

docs-examples/python/multi_bind_example.py

+import taos
+from datetime import datetime
+
+# ANCHOR: bind_batch
+table_tags = {
+    "d1001": ('Beijing.Chaoyang', 2),
+    "d1002": ('Beijing.Chaoyang', 3),
+    "d1003": ('Beijing.Haidian', 2),
+    "d1004": ('Beijing.Haidian', 3)
+}
+
+table_values = {
+    "d1001": [
+        ['2018-10-03 14:38:05.000', '2018-10-03 14:38:15.000', '2018-10-03 14:38:16.800'],
+        [10.3, 12.6, 12.3],
+        [219, 218, 221],
+        [0.31, 0.33, 0.32]
+    ],
+    "d1002": [
+        ['2018-10-03 14:38:16.650'], [10.3], [218], [0.25]
+    ],
+    "d1003": [
+        ['2018-10-03 14:38:05.500', '2018-10-03 14:38:16.600'],
+        [11.8, 13.4],
+        [221, 223],
+        [0.28, 0.29]
+    ],
+    "d1004": [
+        ['2018-10-03 14:38:05.500', '2018-10-03 14:38:06.500'],
+        [10.8, 11.5],
+        [223, 221],
+        [0.29, 0.35]
+    ]
+}
+
+
+def bind_multi_rows(stmt: taos.TaosStmt):
+    """
+    batch bind example
+    """
+    for tb_name in table_values.keys():
+        tags = table_tags[tb_name]
+        tag_params = taos.new_bind_params(2)
+        tag_params[0].binary(tags[0])
+        tag_params[1].int(tags[1])
+        stmt.set_tbname_tags(tb_name, tag_params)
+
+        values = table_values[tb_name]
+        value_params = taos.new_multi_binds(4)
+        value_params[0].timestamp([get_ts(t) for t in values[0]])
+        value_params[1].float(values[1])
+        value_params[2].int(values[2])
+        value_params[3].float(values[3])
+        stmt.bind_param_batch(value_params)
+
+
+def insert_data():
+    conn = taos.connect(database="power")
+    try:
+        stmt = conn.statement("INSERT INTO ? USING meters TAGS(?, ?) VALUES(?, ?, ?, ?)")
+        bind_multi_rows(stmt)
+        stmt.execute()
+        stmt.close()
+    finally:
+        conn.close()
+
+
+# ANCHOR_END: bind_batch
+
+
+def create_stable():
+    conn = taos.connect()
+    try:
+        conn.execute("CREATE DATABASE power")
+        conn.execute("CREATE STABLE power.meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) "
+                     "TAGS (location BINARY(64), groupId INT)")
+    finally:
+        conn.close()
+
+
+def get_ts(ts: str):
+    dt = datetime.strptime(ts, '%Y-%m-%d %H:%M:%S.%f')
+    return int(dt.timestamp() * 1000)
+
+
+if __name__ == '__main__':
+    create_stable()
+    insert_data()

docs-examples/python/native_insert_example.py

+import taos
+
+lines = ["d1001,2018-10-03 14:38:05.000,10.30000,219,0.31000,Beijing.Chaoyang,2",
+         "d1004,2018-10-03 14:38:05.000,10.80000,223,0.29000,Beijing.Haidian,3",
+         "d1003,2018-10-03 14:38:05.500,11.80000,221,0.28000,Beijing.Haidian,2",
+         "d1004,2018-10-03 14:38:06.500,11.50000,221,0.35000,Beijing.Haidian,3",
+         "d1002,2018-10-03 14:38:16.650,10.30000,218,0.25000,Beijing.Chaoyang,3",
+         "d1001,2018-10-03 14:38:15.000,12.60000,218,0.33000,Beijing.Chaoyang,2",
+         "d1001,2018-10-03 14:38:16.800,12.30000,221,0.31000,Beijing.Chaoyang,2",
+         "d1003,2018-10-03 14:38:16.600,13.40000,223,0.29000,Beijing.Haidian,2"]
+
+
+def get_connection() -> taos.TaosConnection:
+    """
+    create connection use firstEp in taos.cfg and use default user and password.
+    """
+    return taos.connect()
+
+
+def create_stable(conn: taos.TaosConnection):
+    conn.execute("CREATE DATABASE power")
+    conn.execute("USE power")
+    conn.execute("CREATE STABLE meters (ts TIMESTAMP, current FLOAT, voltage INT, phase FLOAT) "
+                 "TAGS (location BINARY(64), groupId INT)")
+
+
+# The generated SQL is:
+# INSERT INTO d1001 USING meters TAGS(Beijing.Chaoyang, 2) VALUES ('2018-10-03 14:38:05.000', 10.30000, 219, 0.31000) ('2018-10-03 14:38:15.000', 12.60000, 218, 0.33000) ('2018-10-03 14:38:16.800', 12.30000, 221, 0.31000)
+#             d1002 USING meters TAGS(Beijing.Chaoyang, 3) VALUES ('2018-10-03 14:38:16.650', 10.30000, 218, 0.25000)
+#             d1003 USING meters TAGS(Beijing.Haidian, 2) VALUES ('2018-10-03 14:38:05.500', 11.80000, 221, 0.28000) ('2018-10-03 14:38:16.600', 13.40000, 223, 0.29000)
+#             d1004 USING meters TAGS(Beijing.Haidian, 3) VALUES ('2018-10-03 14:38:05.000', 10.80000, 223, 0.29000) ('2018-10-03 14:38:06.500', 11.50000, 221, 0.35000)
+
+def get_sql():
+    global lines
+    lines = map(lambda line: line.split(','), lines)  # [['d1001', ...]...]
+    lines = sorted(lines, key=lambda ls: ls[0])  # sort by table name
+    sql = "INSERT INTO "
+    tb_name = None
+    for ps in lines:
+        tmp_tb_name = ps[0]
+        if tb_name != tmp_tb_name:
+            tb_name = tmp_tb_name
+            sql += f"{tb_name} USING meters TAGS({ps[5]}, {ps[6]}) VALUES "
+        sql += f"('{ps[1]}', {ps[2]}, {ps[3]}, {ps[4]}) "
+    return sql
+
+
+def insert_data(conn: taos.TaosConnection):
+    sql = get_sql()
+    affected_rows = conn.execute(sql)
+    print("affected_rows", affected_rows)  # 8
+
+
+if __name__ == '__main__':
+    connection = get_connection()
+    try:
+        create_stable(connection)
+        insert_data(connection)
+    finally:
+        connection.close()

docs-examples/python/query_example.py

+import taos
+
+
+# ANCHOR: iter
+def query_api_demo(conn: taos.TaosConnection):
+    result: taos.TaosResult = conn.query("SELECT tbname, * FROM meters LIMIT 2")
+    print("field count:", result.field_count)
+    print("meta of fields[1]:", result.fields[1])
+    print("======================Iterate on result=========================")
+    for row in result:
+        print(row)
+
+
+# field count: 7
+# meta of files[1]: {name: ts, type: 9, bytes: 8}
+# ======================Iterate on result=========================
+# ('d1001', datetime.datetime(2018, 10, 3, 14, 38, 5), 10.300000190734863, 219, 0.3100000023841858, 'Beijing.Chaoyang', 2)
+# ('d1001', datetime.datetime(2018, 10, 3, 14, 38, 15), 12.600000381469727, 218, 0.33000001311302185, 'Beijing.Chaoyang', 2)
+# ANCHOR_END: iter
+
+# ANCHOR: fetch_all
+def fetch_all_demo(conn: taos.TaosConnection):
+    result: taos.TaosResult = conn.query("SELECT ts, current FROM meters LIMIT 2")
+    rows = result.fetch_all_into_dict()
+    print("row count:", result.row_count)
+    print("===============all data===================")
+    print(rows)
+
+
+# row count: 2
+# ===============all data===================
+# [{'ts': datetime.datetime(2018, 10, 3, 14, 38, 5), 'current': 10.300000190734863},
+# {'ts': datetime.datetime(2018, 10, 3, 14, 38, 15), 'current': 12.600000381469727}]
+# ANCHOR_END: fetch_all
+
+if __name__ == '__main__':
+    connection = taos.connect(database="power")
+    try:
+        query_api_demo(connection)
+        fetch_all_demo(connection)
+    finally:
+        connection.close()

docs-examples/python/rest_client_example.py

+from taosrest import RestClient
+
+client = RestClient("localhost", 6041, "root", "taosdata")
+res: dict = client.sql("SELECT ts, current FROM power.meters LIMIT 1")
+print(res)
+
+# output:
+# {'status': 'succ', 'head': ['ts', 'current'], 'column_meta': [['ts', 9, 8], ['current', 6, 4]], 'data': [[datetime.datetime(2018, 10, 3, 14, 38, 5, tzinfo=datetime.timezone(datetime.timedelta(seconds=28800), '+08:00')), 10.3]], 'rows': 1}
+

docs-examples/python/result_set_examples.py

+import taos
+
+conn = taos.connect()
+conn.execute("DROP DATABASE IF EXISTS test")
+conn.execute("CREATE DATABASE test")
+conn.select_db("test")
+conn.execute("CREATE STABLE weather(ts TIMESTAMP, temperature FLOAT) TAGS (location INT)")
+# prepare data
+for i in range(2000):
+    location = str(i % 10)
+    tb = "t" + location
+    conn.execute(f"INSERT INTO {tb} USING weather TAGS({location}) VALUES (now+{i}a, 23.5) (now+{i + 1}a, 23.5)")
+
+result: taos.TaosResult = conn.query("SELECT * FROM weather")
+
+block_index = 0
+blocks: taos.TaosBlocks = result.blocks_iter()
+for rows, length in blocks:
+    print("block ", block_index, " length", length)
+    print("first row in this block:", rows[0])
+    block_index += 1
+
+conn.close()
+
+# possible output:
+# block  0  length 1200
+# first row in this block: (datetime.datetime(2022, 4, 27, 15, 14, 52, 46000), 23.5, 0)
+# block  1  length 1200
+# first row in this block: (datetime.datetime(2022, 4, 27, 15, 14, 52, 76000), 23.5, 3)
+# block  2  length 1200
+# first row in this block: (datetime.datetime(2022, 4, 27, 15, 14, 52, 99000), 23.5, 6)
+# block  3  length 400
+# first row in this block: (datetime.datetime(2022, 4, 27, 15, 14, 52, 122000), 23.5, 9)

docs-examples/python/subscribe_demo.py

+"""
+Python asynchronous subscribe demo.
+run on Linux system with: python3 subscribe_demo.py
+"""
+
+from ctypes import c_void_p
+
+import taos
+import time
+
+
+def query_callback(p_sub, p_result, p_param, code):
+    """
+    :param p_sub: pointer returned by native API -- taos_subscribe
+    :param p_result: pointer to native TAOS_RES
+    :param p_param: None
+    :param code: error code
+    :return: None
+    """
+    print("in callback")
+    result = taos.TaosResult(c_void_p(p_result))
+    # raise exception if error occur
+    result.check_error(code)
+    for row in result.rows_iter():
+        print(row)
+    print(f"{result.row_count} rows consumed.")
+
+
+if __name__ == '__main__':
+    conn = taos.connect()
+    restart = True
+    topic = "topic-meter-current-bg"
+    sql = "select * from power.meters where current > 10"  # Error sql
+    interval = 2000  # consumption interval in microseconds.
+    _ = conn.subscribe(restart, topic, sql, interval, query_callback)
+    # Note: we received the return value as _ above, to avoid the TaosSubscription object to be deleted by gc.
+    while True:
+        time.sleep(10)  # use Ctrl + C to interrupt

docs-examples/python/telnet_line_protocol_example.py

+import taos
+from taos import SmlProtocol, SmlPrecision
+
+# format: <metric> <timestamp> <value> <tagk_1>=<tagv_1>[ <tagk_n>=<tagv_n>]
+lines = ["meters.current 1648432611249 10.3 location=Beijing.Chaoyang groupid=2",
+         "meters.current 1648432611250 12.6 location=Beijing.Chaoyang groupid=2",
+         "meters.current 1648432611249 10.8 location=Beijing.Haidian groupid=3",
+         "meters.current 1648432611250 11.3 location=Beijing.Haidian groupid=3",
+         "meters.voltage 1648432611249 219 location=Beijing.Chaoyang groupid=2",
+         "meters.voltage 1648432611250 218 location=Beijing.Chaoyang groupid=2",
+         "meters.voltage 1648432611249 221 location=Beijing.Haidian groupid=3",
+         "meters.voltage 1648432611250 217 location=Beijing.Haidian groupid=3",
+         ]
+
+
+# create connection use firstEp in taos.cfg.
+def get_connection():
+    return taos.connect()
+
+
+def create_database(conn):
+    conn.execute("CREATE DATABASE test")
+    conn.execute("USE test")
+
+
+def insert_lines(conn):
+    affected_rows = conn.schemaless_insert(
+        lines, SmlProtocol.TELNET_PROTOCOL, SmlPrecision.NOT_CONFIGURED)
+    print(affected_rows)  # 8
+
+
+if __name__ == '__main__':
+    connection = get_connection()
+    try:
+        create_database(connection)
+        insert_lines(connection)
+    finally:
+        connection.close()