使用PreparedStatement访问MySQL数据库
进行增删改查操作
package study;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
public class JDBCdemo {
private final String USERNAME = "root";
private final String PASSWORD = "123456";
private final String URL = "jdbc:mysql://localhost:3306/test?serverTimezone=UTC";
Connection connection = null;
PreparedStatement pStatement = null;
ResultSet rs = null;
public void query() {
try {
Class.forName("com.mysql.cj.jdbc.Driver");
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
connection = DriverManager.getConnection(URL, USERNAME, PASSWORD);
String sql = "select * from user where uname like ?";// 查询
String sql2 = "delete from user where uid=?";// 删除
String sql3 = "update user set uname= ? where uid=?";// 修改
String sql4 = "insert into user values(?,?,?)";// 插入
pStatement = connection.prepareStatement(sql);
// 插入用的数据
// pStatement.setInt(1, 2);
// pStatement.setString(2, "张峰");
// pStatement.setString(3, "女");
// 查询用的数据
pStatement.setString(1, "%峰%");// 模糊查询
rs = pStatement.executeQuery();// 查询
// int executeUpdate= pStatement.executeUpdate();//增删改用的
while (rs.next()) { // 查询用的
System.out.print(rs.getInt("uid") + "\t");
System.out.print(rs.getString("uname") + "\t");
System.out.print(rs.getString("usex") + "\t");
System.out.println("操作成功");
}
// 增删改用的
// if(executeUpdate!=0) {
// System.out.println("操作成功");
// }
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} finally {// 后打开的先关闭
try {
if (rs != null)
rs.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
if (pStatement != null)
pStatement.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
if (connection != null)
connection.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
执行结果如下: