Java中的PreparedStatement对象使用解析

​ String sql = "select * from users where id = ?";
​ String sql = "insert into users(id,name,password,email,birthday) values(?,?,?,?,?)"
​ String sql = "updateaccountset money = money - ? whereid= ?";

​ st = conn.prepareStatement();

​ st.setInt(1,2);

​ rs = st.executeQuery();

package com.test;
import com.test.second.JdbcUtils;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Date;
public class PrepareTest {
    public static void main(String[] args) {
        Connection conn = null;
        PreparedStatement st = null;
        ResultSet rs = null;
        try {
            conn = JdbcUtils.getConnection();
            String sql = "insert into users(id,`name`,`password`,`email`,`birthday`) values(?,?,?,?,?)";
            st = conn.prepareStatement(sql);
            st.setInt(1,1);
            st.setString(2,"cyh");
            st.setString(3,"123456");
            st.setString(4,"1294967895@qq.com");
            // 注意点：sql.Date是数据库中使用的时间，java,sql.Date()
            //       util.Date是java中使用的时间，new Date().getTime()获得当前时间戳
            st.setDate(5,new java.sql.Date(new Date().getTime()));
            // i返回操作数据数
            int i = st.executeUpdate();
            if(i>0){
                System.out.println("插入成功");
            }
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            JdbcUtils.release(conn,st,rs);
        }
    }
}