[JDBC]批处理

一.code

import org.junit.jupiter.api.Test;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;

public class TestBatch {
    @Test
    public void test1()throws Exception{
        //没有用批处理的功能
        long start = System.currentTimeMillis();

        //建立连接
        String url = "jdbc:mysql://localhost:3306/jdbctest";
        String user = "root";
        String pwd = "123456";
        Connection connection = DriverManager.getConnection(url, user, pwd);

        //编写sql
        String sql = "insert into t_department values(null,?,?)";
        PreparedStatement preparedStatement = connection.prepareStatement(sql);
        for(int i=1; i<=2000; i++){
            preparedStatement.setObject(1, "模拟部门名称" + i );
            preparedStatement.setObject(2, "模拟部门简介" + i );
            preparedStatement.executeUpdate();
            //执行2000遍
        }
        preparedStatement.close();
        connection.close();

        long end = System.currentTimeMillis();
        System.out.println("耗时：" +(end-start));
        //耗时：6554
    }

    @Test
    public void test2()throws Exception{
        //使用批处理功能
        long start = System.currentTimeMillis();

/*        MySQL服务器端，默认批处理功能没有开启。需要通过参数告知mysql服务器，开启批处理功能。
        在url后面再加一个参数 rewriteBatchedStatements=true*/
        //建立连接
        String url = "jdbc:mysql://localhost:3306/jdbctest";
        String pwd = "123456";
        String user = "root";
        Connection connection = DriverManager.getConnection(url, user, pwd);

        //编写sql
        String sql = "insert into t_department values(null,?,?)";
        PreparedStatement preparedStatement = connection.prepareStatement(sql);
        for(int i=2001; i<=4000; i++){
            preparedStatement.setObject(1, "模拟部门名称a" + i );
            preparedStatement.setObject(2, "模拟部门简介b" + i );
            preparedStatement.addBatch();//先攒着
        }
        preparedStatement.executeBatch();//执行批处理功能

        preparedStatement.close();
        connection.close();

        long end = System.currentTimeMillis();
        System.out.println("耗时：" +(end-start));//耗时：729
    }
}