package org.bw88;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import com.mysql.jdbc.Connection;
public class conmysql {
public static void main(String[] args) throws Exception {
String conString="jdbc:mysql://localhost:3306/mydb?useSSL=false&serverTimezone=UTC&characterEncoding=utf-8";
String user="root";
String password="root";
Connection conn=(Connection) DriverManager.getConnection(conString, user, password);
/**
* 插入数据,并获取自增ID,获取的是最后一次插入的记录的ID,前提是id是自增的,
*/
/* Statement statement=conn.createStatement();*/
String sql="INSERT INTO user_table(username,password) VALUES(?,?)";
PreparedStatement ps=conn.prepareStatement(sql,Statement.RETURN_GENERATED_KEYS);
ps.setString(1, "tpl");
ps.setString(2, "888");
ps.executeUpdate();
ResultSet rs=ps.getGeneratedKeys();
while(rs.next()) {
int id=rs.getInt(1);//返回指定列的值
System.out.println("自增id="+id);
}
// statement.execute(sql);
/**
* 更新数据
*/
/* Statement statement=conn.createStatement();
String sql="UPDATE user_table SET password='111' WHERE username='16060426'";
//statement.execute(sql);
int i=statement.executeUpdate(sql);
System.out.println(i);*/
/**
* 删除数据
*/
/* Statement statement=conn.createStatement();
String sql="delete from user_table WHERE username='16060426'";
statement.equals(sql);
int i=statement.executeUpdate(sql);
System.out.println(i);*/
/**
* 查找
*/
/* String pass="223";
Statement statement=conn.createStatement();
// String sql="select * from user_table WHERE password='223'";
String sql="select * from user_table WHERE password='"+pass+"'";
ResultSet rs=statement.executeQuery(sql);
while(rs.next()) {
StringBuffer sb=new StringBuffer()
.append("用户名:")
.append(rs.getString("username"))
.append("密码")
.append(rs.getString(2));
System.out.println(sb);
}*/
/**
* prepareStatement 参数查询
*/
/* String pass="223";
String sql="select * from user_table WHERE password=?";
PreparedStatement ps=(PreparedStatement) conn.prepareStatement(sql);
ps.setString(1, pass);
ResultSet rs=ps.executeQuery();
while(rs.next()) {
System.out.println("用户名:"+rs.getString("username"));
}*/
rs.close();
ps.close();
conn.close();
}
}