// TAOS standard API example. The same syntax as MySQL, but only a subet // to compile: gcc -o prepare prepare.c -ltaos #include #include #include #include "taos.h" void taosMsleep(int mseconds); int main(int argc, char *argv[]) { TAOS *taos; TAOS_RES *result; int code; TAOS_STMT *stmt; // connect to server if (argc < 2) { printf("please input server ip \n"); return 0; } taos = taos_connect(argv[1], "root", "taosdata", NULL, 0); if (taos == NULL) { printf("failed to connect to db, reason:%s\n", taos_errstr(taos)); exit(1); } result = taos_query(taos, "drop database demo"); taos_free_result(result); result = taos_query(taos, "create database demo"); code = taos_errno(result); if (code != 0) { printf("failed to create database, reason:%s\n", taos_errstr(result)); taos_free_result(result); exit(1); } taos_free_result(result); result = taos_query(taos, "use demo"); taos_free_result(result); // create table const char* sql = "create table m1 (ts timestamp, b bool, v1 tinyint, v2 smallint, v4 int, v8 bigint, f4 float, f8 double, bin binary(40), blob nchar(10))"; result = taos_query(taos, sql); code = taos_errno(result); if (code != 0) { printf("failed to create table, reason:%s\n", taos_errstr(result)); taos_free_result(result); exit(1); } taos_free_result(result); // sleep for one second to make sure table is created on data node // taosMsleep(1000); // insert 10 records struct { int64_t ts; int8_t b; int8_t v1; int16_t v2; int32_t v4; int64_t v8; float f4; double f8; char bin[40]; char blob[80]; } v = {0}; stmt = taos_stmt_init(taos); TAOS_BIND params[10]; params[0].buffer_type = TSDB_DATA_TYPE_TIMESTAMP; params[0].buffer_length = sizeof(v.ts); params[0].buffer = &v.ts; params[0].length = ¶ms[0].buffer_length; params[0].is_null = NULL; params[1].buffer_type = TSDB_DATA_TYPE_BOOL; params[1].buffer_length = sizeof(v.b); params[1].buffer = &v.b; params[1].length = ¶ms[1].buffer_length; params[1].is_null = NULL; params[2].buffer_type = TSDB_DATA_TYPE_TINYINT; params[2].buffer_length = sizeof(v.v1); params[2].buffer = &v.v1; params[2].length = ¶ms[2].buffer_length; params[2].is_null = NULL; params[3].buffer_type = TSDB_DATA_TYPE_SMALLINT; params[3].buffer_length = sizeof(v.v2); params[3].buffer = &v.v2; params[3].length = ¶ms[3].buffer_length; params[3].is_null = NULL; params[4].buffer_type = TSDB_DATA_TYPE_INT; params[4].buffer_length = sizeof(v.v4); params[4].buffer = &v.v4; params[4].length = ¶ms[4].buffer_length; params[4].is_null = NULL; params[5].buffer_type = TSDB_DATA_TYPE_BIGINT; params[5].buffer_length = sizeof(v.v8); params[5].buffer = &v.v8; params[5].length = ¶ms[5].buffer_length; params[5].is_null = NULL; params[6].buffer_type = TSDB_DATA_TYPE_FLOAT; params[6].buffer_length = sizeof(v.f4); params[6].buffer = &v.f4; params[6].length = ¶ms[6].buffer_length; params[6].is_null = NULL; params[7].buffer_type = TSDB_DATA_TYPE_DOUBLE; params[7].buffer_length = sizeof(v.f8); params[7].buffer = &v.f8; params[7].length = ¶ms[7].buffer_length; params[7].is_null = NULL; params[8].buffer_type = TSDB_DATA_TYPE_BINARY; params[8].buffer_length = sizeof(v.bin); params[8].buffer = v.bin; params[8].length = ¶ms[8].buffer_length; params[8].is_null = NULL; strcpy(v.blob, "一二三四五六七八九十"); params[9].buffer_type = TSDB_DATA_TYPE_NCHAR; params[9].buffer_length = strlen(v.blob); params[9].buffer = v.blob; params[9].length = ¶ms[9].buffer_length; params[9].is_null = NULL; int is_null = 1; sql = "insert into m1 values(?,?,?,?,?,?,?,?,?,?)"; code = taos_stmt_prepare(stmt, sql, 0); if (code != 0){ printf("failed to execute taos_stmt_prepare. code:0x%x\n", code); } v.ts = 1591060628000; for (int i = 0; i < 10; ++i) { v.ts += 1; for (int j = 1; j < 10; ++j) { params[j].is_null = ((i == j) ? &is_null : 0); } v.b = (int8_t)i % 2; v.v1 = (int8_t)i; v.v2 = (int16_t)(i * 2); v.v4 = (int32_t)(i * 4); v.v8 = (int64_t)(i * 8); v.f4 = (float)(i * 40); v.f8 = (double)(i * 80); for (int j = 0; j < sizeof(v.bin) - 1; ++j) { v.bin[j] = (char)(i + '0'); } taos_stmt_bind_param(stmt, params); taos_stmt_add_batch(stmt); } if (taos_stmt_execute(stmt) != 0) { printf("failed to execute insert statement.\n"); exit(1); } taos_stmt_close(stmt); // query the records stmt = taos_stmt_init(taos); taos_stmt_prepare(stmt, "SELECT * FROM m1 WHERE v1 > ? AND v2 < ?", 0); v.v1 = 5; v.v2 = 15; taos_stmt_bind_param(stmt, params + 2); if (taos_stmt_execute(stmt) != 0) { printf("failed to execute select statement.\n"); exit(1); } result = taos_stmt_use_result(stmt); TAOS_ROW row; int rows = 0; int num_fields = taos_num_fields(result); TAOS_FIELD *fields = taos_fetch_fields(result); char temp[256]; // fetch the records row by row while ((row = taos_fetch_row(result))) { rows++; taos_print_row(temp, row, fields, num_fields); printf("%s\n", temp); } if (rows == 2) { printf("two rows are fetched as expectation\n"); } else { printf("expect two rows, but %d rows are fetched\n", rows); } taos_free_result(result); taos_stmt_close(stmt); return 0; }