src/UserGuide/V1.0.x/API/Programming-JDBC.md - iotdb-docs - Git at Google

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 ## JDBC

 *NOTICE: CURRENTLY, JDBC IS USED FOR CONNECTING SOME THIRD-PART TOOLS.
 IT CAN NOT PROVIDE HIGH THROUGHPUT FOR WRITE OPERATIONS.
 PLEASE USE [JAVA NATIVE API](https://iotdb.apache.org/UserGuide/Master/API/Programming-Java-Native-API.html) INSTEAD*

 ### Dependencies

 * JDK >= 1.8
 * Maven >= 3.6


 ### Installation

 In root directory:

 ```shell
 mvn clean install -pl jdbc -am -Dmaven.test.skip=true
 ```


 ### Use IoTDB JDBC with Maven

 ```xml
 <dependencies>
     <dependency>
       <groupId>org.apache.iotdb</groupId>
       <artifactId>iotdb-jdbc</artifactId>
       <version>0.12.0</version>
     </dependency>
 </dependencies>
 ```


 ### Coding Examples

 This chapter provides an example of how to open a database connection, execute a SQL query, and display the results.

 It requires including the packages containing the JDBC classes needed for database programming.

 **NOTE: For faster insertion, the insertTablet() in Session is recommended.**

 ```java
 import java.sql.*;
 import org.apache.iotdb.jdbc.IoTDBSQLException;

 public class JDBCExample {
   /**
    * Before executing a SQL statement with a Statement object, you need to create a Statement object using the createStatement() method of the Connection object.
    * After creating a Statement object, you can use its execute() method to execute a SQL statement
    * Finally, remember to close the 'statement' and 'connection' objects by using their close() method
    * For statements with query results, we can use the getResultSet() method of the Statement object to get the result set.
    */
   public static void main(String[] args) throws SQLException {
     Connection connection = getConnection();
     if (connection == null) {
       System.out.println("get connection defeat");
       return;
     }
     Statement statement = connection.createStatement();
     //Create database
     try {
       statement.execute("CREATE DATABASE root.demo");
     }catch (IoTDBSQLException e){
       System.out.println(e.getMessage());
     }


     //SHOW DATABASES
     statement.execute("SHOW DATABASES");
     outputResult(statement.getResultSet());

     //Create time series
     //Different data type has different encoding methods. Here use INT32 as an example
     try {
       statement.execute("CREATE TIMESERIES root.demo.s0 WITH DATATYPE=INT32,ENCODING=RLE;");
     }catch (IoTDBSQLException e){
       System.out.println(e.getMessage());
     }
     //Show time series
     statement.execute("SHOW TIMESERIES root.demo");
     outputResult(statement.getResultSet());
     //Show devices
     statement.execute("SHOW DEVICES");
     outputResult(statement.getResultSet());
     //Count time series
     statement.execute("COUNT TIMESERIES root");
     outputResult(statement.getResultSet());
     //Count nodes at the given level
     statement.execute("COUNT NODES root LEVEL=3");
     outputResult(statement.getResultSet());
     //Count timeseries group by each node at the given level
     statement.execute("COUNT TIMESERIES root GROUP BY LEVEL=3");
     outputResult(statement.getResultSet());


     //Execute insert statements in batch
     statement.addBatch("insert into root.demo(timestamp,s0) values(1,1);");
     statement.addBatch("insert into root.demo(timestamp,s0) values(1,1);");
     statement.addBatch("insert into root.demo(timestamp,s0) values(2,15);");
     statement.addBatch("insert into root.demo(timestamp,s0) values(2,17);");
     statement.addBatch("insert into root.demo(timestamp,s0) values(4,12);");
     statement.executeBatch();
     statement.clearBatch();

     //Full query statement
     String sql = "select * from root.demo";
     ResultSet resultSet = statement.executeQuery(sql);
     System.out.println("sql: " + sql);
     outputResult(resultSet);

     //Exact query statement
     sql = "select s0 from root.demo where time = 4;";
     resultSet= statement.executeQuery(sql);
     System.out.println("sql: " + sql);
     outputResult(resultSet);

     //Time range query
     sql = "select s0 from root.demo where time >= 2 and time < 5;";
     resultSet = statement.executeQuery(sql);
     System.out.println("sql: " + sql);
     outputResult(resultSet);

     //Aggregate query
     sql = "select count(s0) from root.demo;";
     resultSet = statement.executeQuery(sql);
     System.out.println("sql: " + sql);
     outputResult(resultSet);

     //Delete time series
     statement.execute("delete timeseries root.demo.s0");

     //close connection
     statement.close();
     connection.close();
   }

   public static Connection getConnection() {
     // JDBC driver name and database URL
     String driver = "org.apache.iotdb.jdbc.IoTDBDriver";
     String url = "jdbc:iotdb://127.0.0.1:6667/";
     // set rpc compress mode
     // String url = "jdbc:iotdb://127.0.0.1:6667?rpc_compress=true";

     // Database credentials
     String username = "root";
     String password = "root";

     Connection connection = null;
     try {
       Class.forName(driver);
       connection = DriverManager.getConnection(url, username, password);
     } catch (ClassNotFoundException e) {
       e.printStackTrace();
     } catch (SQLException e) {
       e.printStackTrace();
     }
     return connection;
   }

   /**
    * This is an example of outputting the results in the ResultSet
    */
   private static void outputResult(ResultSet resultSet) throws SQLException {
     if (resultSet != null) {
       System.out.println("--------------------------");
       final ResultSetMetaData metaData = resultSet.getMetaData();
       final int columnCount = metaData.getColumnCount();
       for (int i = 0; i < columnCount; i++) {
         System.out.print(metaData.getColumnLabel(i + 1) + " ");
       }
       System.out.println();
       while (resultSet.next()) {
         for (int i = 1; ; i++) {
           System.out.print(resultSet.getString(i));
           if (i < columnCount) {
             System.out.print(", ");
           } else {
             System.out.println();
             break;
           }
         }
       }
       System.out.println("--------------------------\n");
     }
   }
 }
 ```

 The parameter `version` can be used in the url:
 ````java
 String url = "jdbc:iotdb://127.0.0.1:6667?version=V_1_0";
 ````
 The parameter `version` represents the SQL semantic version used by the client, which is used to be compatible with the SQL semantics of 0.12 when upgrading 0.13. The possible values are: `V_0_12`, `V_0_13`, `V_1_0`.
	<!--

	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.

	-->

	## JDBC

	*NOTICE: CURRENTLY, JDBC IS USED FOR CONNECTING SOME THIRD-PART TOOLS.
	IT CAN NOT PROVIDE HIGH THROUGHPUT FOR WRITE OPERATIONS.
	PLEASE USE [JAVA NATIVE API](https://iotdb.apache.org/UserGuide/Master/API/Programming-Java-Native-API.html) INSTEAD*

	### Dependencies

	* JDK >= 1.8
	* Maven >= 3.6



	### Installation

	In root directory:

	```shell
	mvn clean install -pl jdbc -am -Dmaven.test.skip=true
	```



	### Use IoTDB JDBC with Maven

	```xml
	<dependencies>
	<dependency>
	<groupId>org.apache.iotdb</groupId>
	<artifactId>iotdb-jdbc</artifactId>
	<version>0.12.0</version>
	</dependency>
	</dependencies>
	```



	### Coding Examples

	This chapter provides an example of how to open a database connection, execute a SQL query, and display the results.

	It requires including the packages containing the JDBC classes needed for database programming.

	NOTE: For faster insertion, the insertTablet() in Session is recommended.

	```java
	import java.sql.*;
	import org.apache.iotdb.jdbc.IoTDBSQLException;

	public class JDBCExample {
	/**
	* Before executing a SQL statement with a Statement object, you need to create a Statement object using the createStatement() method of the Connection object.
	* After creating a Statement object, you can use its execute() method to execute a SQL statement
	* Finally, remember to close the 'statement' and 'connection' objects by using their close() method
	* For statements with query results, we can use the getResultSet() method of the Statement object to get the result set.
	*/
	public static void main(String[] args) throws SQLException {
	Connection connection = getConnection();
	if (connection == null) {
	System.out.println("get connection defeat");
	return;
	}
	Statement statement = connection.createStatement();
	//Create database
	try {
	statement.execute("CREATE DATABASE root.demo");
	}catch (IoTDBSQLException e){
	System.out.println(e.getMessage());
	}


	//SHOW DATABASES
	statement.execute("SHOW DATABASES");
	outputResult(statement.getResultSet());

	//Create time series
	//Different data type has different encoding methods. Here use INT32 as an example
	try {
	statement.execute("CREATE TIMESERIES root.demo.s0 WITH DATATYPE=INT32,ENCODING=RLE;");
	}catch (IoTDBSQLException e){
	System.out.println(e.getMessage());
	}
	//Show time series
	statement.execute("SHOW TIMESERIES root.demo");
	outputResult(statement.getResultSet());
	//Show devices
	statement.execute("SHOW DEVICES");
	outputResult(statement.getResultSet());
	//Count time series
	statement.execute("COUNT TIMESERIES root");
	outputResult(statement.getResultSet());
	//Count nodes at the given level
	statement.execute("COUNT NODES root LEVEL=3");
	outputResult(statement.getResultSet());
	//Count timeseries group by each node at the given level
	statement.execute("COUNT TIMESERIES root GROUP BY LEVEL=3");
	outputResult(statement.getResultSet());


	//Execute insert statements in batch
	statement.addBatch("insert into root.demo(timestamp,s0) values(1,1);");
	statement.addBatch("insert into root.demo(timestamp,s0) values(1,1);");
	statement.addBatch("insert into root.demo(timestamp,s0) values(2,15);");
	statement.addBatch("insert into root.demo(timestamp,s0) values(2,17);");
	statement.addBatch("insert into root.demo(timestamp,s0) values(4,12);");
	statement.executeBatch();
	statement.clearBatch();

	//Full query statement
	String sql = "select * from root.demo";
	ResultSet resultSet = statement.executeQuery(sql);
	System.out.println("sql: " + sql);
	outputResult(resultSet);

	//Exact query statement
	sql = "select s0 from root.demo where time = 4;";
	resultSet= statement.executeQuery(sql);
	System.out.println("sql: " + sql);
	outputResult(resultSet);

	//Time range query
	sql = "select s0 from root.demo where time >= 2 and time < 5;";
	resultSet = statement.executeQuery(sql);
	System.out.println("sql: " + sql);
	outputResult(resultSet);

	//Aggregate query
	sql = "select count(s0) from root.demo;";
	resultSet = statement.executeQuery(sql);
	System.out.println("sql: " + sql);
	outputResult(resultSet);

	//Delete time series
	statement.execute("delete timeseries root.demo.s0");

	//close connection
	statement.close();
	connection.close();
	}

	public static Connection getConnection() {
	// JDBC driver name and database URL
	String driver = "org.apache.iotdb.jdbc.IoTDBDriver";
	String url = "jdbc:iotdb://127.0.0.1:6667/";
	// set rpc compress mode
	// String url = "jdbc:iotdb://127.0.0.1:6667?rpc_compress=true";

	// Database credentials
	String username = "root";
	String password = "root";

	Connection connection = null;
	try {
	Class.forName(driver);
	connection = DriverManager.getConnection(url, username, password);
	} catch (ClassNotFoundException e) {
	e.printStackTrace();
	} catch (SQLException e) {
	e.printStackTrace();
	}
	return connection;
	}

	/**
	* This is an example of outputting the results in the ResultSet
	*/
	private static void outputResult(ResultSet resultSet) throws SQLException {
	if (resultSet != null) {
	System.out.println("--------------------------");
	final ResultSetMetaData metaData = resultSet.getMetaData();
	final int columnCount = metaData.getColumnCount();
	for (int i = 0; i < columnCount; i++) {
	System.out.print(metaData.getColumnLabel(i + 1) + " ");
	}
	System.out.println();
	while (resultSet.next()) {
	for (int i = 1; ; i++) {
	System.out.print(resultSet.getString(i));
	if (i < columnCount) {
	System.out.print(", ");
	} else {
	System.out.println();
	break;
	}
	}
	}
	System.out.println("--------------------------\n");
	}
	}
	}
	```

	The parameter `version` can be used in the url:
	````java
	String url = "jdbc:iotdb://127.0.0.1:6667?version=V_1_0";
	````
	The parameter `version` represents the SQL semantic version used by the client, which is used to be compatible with the SQL semantics of 0.12 when upgrading 0.13. The possible values are: `V_0_12`, `V_0_13`, `V_1_0`.