PHP + MySQL 基本函数及实例操作

连接 MySQL：mysqli_connet()

//@mysqli_connect('localhost','root','985211',"zoo") or die("连接数据库失败");
//mysqli_connect("MySQL服务器地址","用户名","用户密码","连接的数据库名")
mysqli_connect("localhost","root","985211","zoo");

连接数据库：mysqli_select_db()

$db = mysqli_connect("localhost","root","985211"); 
//mysqli_select_db(数据库服务器连接的对象,"更改后的数据库名")
mysqli_select_db($db,"zoo");

关闭 MySQL 连接：mysqli_close()

//关闭MySQL连接  mysqli_close("关闭的数据库连接对象")
mysqli_close($db);

执行 SQL 语句：mysqli_query()

//执行SQL语句  mysqli_query(数据库服务器连接的对象,"执行的SQL语句")
mysqli_query($db,"");

例：

<?php
    $db = mysqli_connect("localhost","root","985211","zoo");
    $sql_one = "insert into qjy(id,name,age,salary) value (10007,'zc',20,200);";    //执行的sql语句
    if (mysqli_query($db,$sql_one)){    //mysqli_query()函数返回布尔值
        echo "添加信息成功<br/>";
    }else{
        echo "添加信息失败<br/>";
    }
    $sql_two = "delete from qjy where id=10007;";
    if (mysqli_query($db,$sql_two)){
        echo "删除执行成功<br/>";
    }else{
        echo "删除执行失败<br/>";
    }
    $sql_three = "update qjy set name='wll' where id='10001';";
    if (mysqli_query($db,$sql_three)){
        echo "修改数据成功";
    }else{
        echo "修改数据失败";
    }
    /*运行结果：
        添加信息成功
        删除执行成功
        修改数据成功
    */

在MySQL中输入 select * from qjy; 来查询表的变化

//执行sql语句1
mysql> select * from qjy;
+-------+------+-----+--------+
| id    | name | age | salary |
+-------+------+-----+--------+
| 10001 | qjy  |  19 | 800.00 |
| 10002 | hja  |  20 | 700.00 |
| 10003 | lsz  |  18 | 600.00 |
| 10004 | fxf  |  19 | 500.00 |
| 10005 | ycy  |  20 | 400.00 |
| 10006 | zgx  |  20 | 300.00 |
| 10007 | zc   |  20 | 200.00 |
+-------+------+-----+--------+
7 rows in set (0.00 sec)

//执行sql语句2
mysql> select * from qjy;
+-------+------+-----+--------+
| id    | name | age | salary |
+-------+------+-----+--------+
| 10001 | qjy  |  19 | 800.00 |
| 10002 | hja  |  20 | 700.00 |
| 10003 | lsz  |  18 | 600.00 |
| 10004 | fxf  |  19 | 500.00 |
| 10005 | ycy  |  20 | 400.00 |
| 10006 | zgx  |  20 | 300.00 |
+-------+------+-----+--------+
6 rows in set (0.00 sec)

//执行sql语句3
mysql> select * from qjy;
+-------+------+-----+--------+
| id    | name | age | salary |
+-------+------+-----+--------+
| 10001 | wll  |  19 | 800.00 |
| 10002 | hja  |  20 | 700.00 |
| 10003 | lsz  |  18 | 600.00 |
| 10004 | fxf  |  19 | 500.00 |
| 10005 | ycy  |  20 | 400.00 |
| 10006 | zgx  |  20 | 300.00 |
+-------+------+-----+--------+
6 rows in set (0.00 sec)

PHP + MySQL 基本函数及实例操作

猜你喜欢