黑马day10 增多&删除&更新到数据库mysql

黑马day10 增加&删除&更新到数据库mysql

下面是在day10数据库下的表user进行操作的。

如果是更改了数据那么就使用Statement 中的executeUpdate()方法。如果是查询就使用executeQuery()方法.

案例：

package cn.itheima.jdbc;

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

import org.junit.Test;

import cn.itheima.utils.JDBCUtils;

public class JDBCDemo4 {
	private static Connection con=null;
	private static Statement sta=null;
	private static ResultSet rs=null;
			
	@Test
	public void add(){
		try {
			con=JDBCUtils.getConnection();
			sta=con.createStatement();
			sta.executeUpdate("insert into user values(3,'韩玮',0,'1996-02-01')");
		} catch (SQLException e) {
			e.printStackTrace();
			throw new RuntimeException();
		}finally{
			JDBCUtils.closeResource(rs, sta, con);
		}
	}
	@Test
	public void find(){
		try {
			con=JDBCUtils.getConnection();
			sta=con.createStatement();
			rs=sta.executeQuery("select * from user where name='李卫康'");
			while(rs.next()){
				String name = rs.getString("name");
				System.out.println(name);
			}
		} catch (SQLException e) {
			e.printStackTrace();
			throw new RuntimeException();
		}finally{
			JDBCUtils.closeResource(rs, sta, con);
		}
	}
	@Test
	public void update(){
		try {
			con=JDBCUtils.getConnection();
			sta=con.createStatement();
			sta.executeUpdate("update user set gender=0 where name='李卫康'");
		} catch (SQLException e) {
			e.printStackTrace();
			throw new RuntimeException();
		}finally{
			JDBCUtils.closeResource(rs, sta, con);
		}
	}
	@Test
	public void delete(){
		try {
			con=JDBCUtils.getConnection();
			sta=con.createStatement();
			sta.executeUpdate("delete from user where name='程崇树'");
		} catch (SQLException e) {
			e.printStackTrace();
			throw new RuntimeException();
		}finally{
			JDBCUtils.closeResource(rs, sta, con);
		}
	}
}