提交 6c134d4c 编写于 作者: D dingbo

docs: connect

上级 48820d71
......@@ -76,18 +76,7 @@ To obtain the value of JDBC URL, please log in [TDengine Cloud](https://cloud.td
Code bellow get JDBC URL from environment variables first and then create a `Connection` object, witch is a standard JDBC Connection object.
```java
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public class ConnectCloudExample {
public static void main(String[] args) throws SQLException {
String jdbcUrl = System.getenv("TDENGINE_JDBC_URL");
Connection conn = DriverManager.getConnection(jdbcUrl);
conn.close();
}
}
{{#include docs/examples/java/src/main/java/com/taos/example/ConnectCloudExample.java:connect}}
```
The client connection is then established. For how to write data and query data using the connection, please refer to [usage-examples](https://docs.tdengine.com/reference/connector/java#usage-examples).
\ No newline at end of file
package com.taos.example;
import com.taosdata.jdbc.TSDBDriver;
// ANCHOR: connect
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.util.Properties;
public class ConnectCloudExample {
public static void main(String[] args) throws SQLException {
String host = System.getenv("TDENGINE_CLOUD_HOST");
String port = System.getenv("TDENGINE_CLOUD_PORT");
String token = System.getenv("TDENGINE_CLOUD_TOKEN");
String user = System.getenv("TDENGINE_USER_NAME");
String password = System.getenv("TDENGINE_PASSWORD");
String jdbcUrl = String.format("jdbc:TAOS-RS://%s:%s?user=%s&password=%s", host, port, user, password);
Properties connProps = new Properties();
connProps.setProperty(TSDBDriver.PROPERTY_KEY_TOKEN, token);
String jdbcUrl = System.getenv("TDENGINE_JDBC_URL");
Connection conn = DriverManager.getConnection(jdbcUrl);
System.out.println("Connected");
conn.close();
}
}
// ANCHOR_END: connect
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 a specified database named "dbName".
\ No newline at end of file
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\": \"California.SanFrancisco\", \"groupid\": 2}}," +
" {\"metric\": \"meters.voltage\", \"timestamp\": 1648432611249, \"value\": 219, \"tags\": {\"location\": \"California.LosAngeles\", \"groupid\": 1}}, " +
"{\"metric\": \"meters.current\", \"timestamp\": 1648432611250, \"value\": 12.6, \"tags\": {\"location\": \"California.SanFrancisco\", \"groupid\": 2}}," +
" {\"metric\": \"meters.voltage\", \"timestamp\": 1648432611250, \"value\": 221, \"tags\": {\"location\": \"California.LosAngeles\", \"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);
}
}
}
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=California.LosAngeles,groupid=2 current=11.8,voltage=221,phase=0.28 1648432611249000", // micro
// seconds
"meters,location=California.LosAngeles,groupid=2 current=13.4,voltage=223,phase=0.29 1648432611249500",
"meters,location=California.LosAngeles,groupid=3 current=10.8,voltage=223,phase=0.29 1648432611249300",
"meters,location=California.LosAngeles,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);
}
}
}
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
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,California.SanFrancisco,2",
"d1001,2018-10-03 14:38:15.000,12.60000,218,0.33000,California.SanFrancisco,2",
"d1001,2018-10-03 14:38:16.800,12.30000,221,0.31000,California.SanFrancisco,2",
"d1002,2018-10-03 14:38:16.650,10.30000,218,0.25000,California.SanFrancisco,3",
"d1003,2018-10-03 14:38:05.500,11.80000,221,0.28000,California.LosAngeles,2",
"d1003,2018-10-03 14:38:16.600,13.40000,223,0.29000,California.LosAngeles,2",
"d1004,2018-10-03 14:38:05.000,10.80000,223,0.29000,California.LosAngeles,3",
"d1004,2018-10-03 14:38:06.500,11.50000,221,0.35000,California.LosAngeles,3"
);
}
/**
* The generated SQL is:
* INSERT INTO power.d1001 USING power.meters TAGS(California.SanFrancisco, 2) VALUES('2018-10-03 14:38:05.000',10.30000,219,0.31000)
* power.d1001 USING power.meters TAGS(California.SanFrancisco, 2) VALUES('2018-10-03 14:38:15.000',12.60000,218,0.33000)
* power.d1001 USING power.meters TAGS(California.SanFrancisco, 2) VALUES('2018-10-03 14:38:16.800',12.30000,221,0.31000)
* power.d1002 USING power.meters TAGS(California.SanFrancisco, 3) VALUES('2018-10-03 14:38:16.650',10.30000,218,0.25000)
* power.d1003 USING power.meters TAGS(California.LosAngeles, 2) VALUES('2018-10-03 14:38:05.500',11.80000,221,0.28000)
* power.d1003 USING power.meters TAGS(California.LosAngeles, 2) VALUES('2018-10-03 14:38:16.600',13.40000,223,0.29000)
* power.d1004 USING power.meters TAGS(California.LosAngeles, 3) VALUES('2018-10-03 14:38:05.000',10.80000,223,0.29000)
* power.d1004 USING power.meters TAGS(California.LosAngeles, 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();
}
}
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 California.LosAngeles
// 219.0 California.SanFrancisco
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,California.SanFrancisco,2",
"d1001,2018-10-03 14:38:15.000,12.60000,218,0.33000,California.SanFrancisco,2",
"d1001,2018-10-03 14:38:16.800,12.30000,221,0.31000,California.SanFrancisco,2",
"d1002,2018-10-03 14:38:16.650,10.30000,218,0.25000,California.SanFrancisco,3",
"d1003,2018-10-03 14:38:05.500,11.80000,221,0.28000,California.LosAngeles,2",
"d1003,2018-10-03 14:38:16.600,13.40000,223,0.29000,California.LosAngeles,2",
"d1004,2018-10-03 14:38:05.000,10.80000,223,0.29000,California.LosAngeles,3",
"d1004,2018-10-03 14:38:06.500,11.50000,221,0.35000,California.LosAngeles,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();
}
}
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
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=California.SanFrancisco groupid=2",
"meters.current 1648432611250 12.6 location=California.SanFrancisco groupid=2",
"meters.current 1648432611249 10.8 location=California.LosAngeles groupid=3",
"meters.current 1648432611250 11.3 location=California.LosAngeles groupid=3",
"meters.voltage 1648432611249 219 location=California.SanFrancisco groupid=2",
"meters.voltage 1648432611250 218 location=California.SanFrancisco groupid=2",
"meters.voltage 1648432611249 221 location=California.LosAngeles groupid=3",
"meters.voltage 1648432611250 217 location=California.LosAngeles 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);
}
}
}
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
}
......@@ -9,6 +9,8 @@ url = os.environ["TDENGINE_CLOUD_URL"]
token = os.environ["TDENGINE_CLOUD_TOKEN"]
conn = taosrest.connect(url=url, token=token)
# test the connection by getting version info
print("server version:", conn.server_info)
# ANCHOR_END: connect
# ANCHOR: basic
from taosrest import TaosRestCursor
......
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