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The IoTDB JDBC provides a standardized way to interact with the IoTDB database, allowing users to execute SQL statements from Java programs for managing databases and time-series data. It supports operations such as connecting to the database, creating, querying, updating, and deleting data, as well as batch insertion and querying of time-series data.

Note: The current JDBC implementation is designed primarily for integration with third-party tools. High-performance writing may not be achieved when using JDBC for insert operations. For Java applications, it is recommended to use the JAVA Native API for optimal performance.

Prerequisites

Environment Requirements

  • JDK: Version 1.8 or higher
  • Maven: Version 3.6 or higher

Adding Maven Dependencies

Add the following dependency to your Maven pom.xml file:

<dependencies>
    <dependency>
      <groupId>org.apache.iotdb</groupId>
      <artifactId>iotdb-jdbc</artifactId>
      <version>2.0.1-beta</version>
    </dependency>
</dependencies>

Read and Write Operations

Write Operations: Perform database operations such as inserting data, creating databases, and creating time-series using the execute method.

Read Operations: Execute queries using the executeQuery method and retrieve results via the ResultSet object.

Method Overview

Method Name Description Parameters Return Value
Class.forName(String driver) Loads the JDBC driver class driver: Name of the JDBC driver class Class: Loaded class object
DriverManager.getConnection(String url, String username, String password) Establishes a database connection url: Database URL username: Username password: Password Connection: Database connection object
Connection.createStatement() Creates a Statement object for executing SQL statements None Statement: SQL execution object
Statement.execute(String sql) Executes a non-query SQL statement sql: SQL statement to execute boolean: Indicates if a ResultSet is returned
Statement.executeQuery(String sql) Executes a query SQL statement and retrieves the result set sql: SQL query statement ResultSet: Query result set
ResultSet.getMetaData() Retrieves metadata of the result set None ResultSetMetaData: Metadata object
ResultSet.next() Moves to the next row in the result set None boolean: Whether the move was successful
ResultSet.getString(int columnIndex) Retrieves the string value of a specified column columnIndex: Column index (starting from 1) String: Column value

Sample Code

Note: When using the Table Model, you must specify the sql_dialect parameter as table in the URL. Example:

String url = "jdbc:iotdb://127.0.0.1:6667?sql_dialect=table";

You can find the full example code at GitHub Repository.

Here is an excerpt of the sample code:

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.iotdb;

import org.apache.iotdb.jdbc.IoTDBSQLException;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;

public class TableModelJDBCExample {

  private static final Logger LOGGER = LoggerFactory.getLogger(TableModelJDBCExample.class);

  public static void main(String[] args) throws ClassNotFoundException, SQLException {
    Class.forName("org.apache.iotdb.jdbc.IoTDBDriver");

    // don't specify database in url
    try (Connection connection =
            DriverManager.getConnection(
                "jdbc:iotdb://127.0.0.1:6667?sql_dialect=table", "root", "root");
        Statement statement = connection.createStatement()) {

      statement.execute("CREATE DATABASE test1");
      statement.execute("CREATE DATABASE test2");

      statement.execute("use test2");

      // or use full qualified table name
      statement.execute(
          "create table test1.table1(region_id STRING ID, plant_id STRING ID, device_id STRING ID, model STRING ATTRIBUTE, temperature FLOAT MEASUREMENT, humidity DOUBLE MEASUREMENT) with (TTL=3600000)");

      statement.execute(
          "create table table2(region_id STRING ID, plant_id STRING ID, color STRING ATTRIBUTE, temperature FLOAT MEASUREMENT, speed DOUBLE MEASUREMENT) with (TTL=6600000)");

      // show tables from current database
      try (ResultSet resultSet = statement.executeQuery("SHOW TABLES")) {
        ResultSetMetaData metaData = resultSet.getMetaData();
        System.out.println(metaData.getColumnCount());
        while (resultSet.next()) {
          System.out.println(resultSet.getString(1) + ", " + resultSet.getInt(2));
        }
      }

      // show tables by specifying another database
      // using SHOW tables FROM
      try (ResultSet resultSet = statement.executeQuery("SHOW TABLES FROM test1")) {
        ResultSetMetaData metaData = resultSet.getMetaData();
        System.out.println(metaData.getColumnCount());
        while (resultSet.next()) {
          System.out.println(resultSet.getString(1) + ", " + resultSet.getInt(2));
        }
      }

    } catch (IoTDBSQLException e) {
      LOGGER.error("IoTDB Jdbc example error", e);
    }

    // specify database in url
    try (Connection connection =
            DriverManager.getConnection(
                "jdbc:iotdb://127.0.0.1:6667/test1?sql_dialect=table", "root", "root");
        Statement statement = connection.createStatement()) {
      // show tables from current database test1
      try (ResultSet resultSet = statement.executeQuery("SHOW TABLES")) {
        ResultSetMetaData metaData = resultSet.getMetaData();
        System.out.println(metaData.getColumnCount());
        while (resultSet.next()) {
          System.out.println(resultSet.getString(1) + ", " + resultSet.getInt(2));
        }
      }

      // change database to test2
      statement.execute("use test2");

      try (ResultSet resultSet = statement.executeQuery("SHOW TABLES")) {
        ResultSetMetaData metaData = resultSet.getMetaData();
        System.out.println(metaData.getColumnCount());
        while (resultSet.next()) {
          System.out.println(resultSet.getString(1) + ", " + resultSet.getInt(2));
        }
      }
    }
  }
}