php mysqli 连接数据库 有大用

mysqli连接 数据库查询单条数据

<?php

// 假定数据库用户名：root，密码：root，数据库：tianxiangphp_v1.2 

$con=mysqli_connect("localhost","root","root","tianxiangphp_v1.2");

if (mysqli_connect_errno($con))

{

    echo "连接 MySQL 失败: " . mysqli_connect_error();

}

// 执行查询

$res = $con->query("SELECT * FROM userlist");

$data = mysqli_fetch_array($res);

echo "<pre>";

var_dump($data);

mysqli_close($con);

?>

query()与mysqli_query()使用

放在函数内与函数外

mysqli_query($con,”sql语句”);

$con->query(”sql语句”);

查询多条数据fetch_all()

<?php

// 假定数据库用户名：root，密码：root，数据库：tianxiangphp_v1.2

$con=mysqli_connect("localhost","root","root","tianxiangphp_v1.2");

if (mysqli_connect_errno($con))

{

    echo "连接 MySQL 失败: " . mysqli_connect_error();

}

// 执行查询

$res = $con->query("SELECT * FROM userlist");

$data = $res->fetch_all(MYSQLI_ASSOC);

echo "<pre>";

var_dump($data);

mysqli_close($con);

?>

插入单条数据mysqli_query()或query()

为true则插入成功

注意：需要插入多条可循环遍历插入

<?php

// 假定数据库用户名：root，密码：root，数据库：tianxiangphp_v1.2

$con=mysqli_connect("localhost","root","root","tianxiangphp_v1.2");

if (mysqli_connect_errno($con))

{

    echo "连接 MySQL 失败: " . mysqli_connect_error();

}

// 执行插入

$res = mysqli_query($con,"INSERT INTO userlist(mb_type,qy_userid) VALUES (1,666)");

if ($res == TRUE) {

    echo "user entry saved successfully.";

} else {

    echo "INSERT attempt failed" ;

}

?>

修改数据mysqli_query()或query()

$res = mysqli_query($con,"UPDATE userlist SET `mbid`=77 WHERE userid = 1894");

if ($res == TRUE) {

    echo "user entry saved successfully.";

} else {

    echo "update attempt failed" ;

}

删除数据mysqli_query()或query()

mysqli_query($con,”sql语句”);

$con->query(”sql语句”);

$res = mysqli_query($con,"DELETE FROM userlist WHERE userid = 1895");

统计表总条数

$res = $con->query("SELECT * FROM yzm_user");

//统计总条数

$count = mysqli_num_rows($res);

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版权声明：本文为CSDN博主「刘远山」的原创文章，遵循CC 4.0 BY-SA版权协议，转载请附上原文出处链接及本声明。

来自 https://blog.csdn.net/weixin_39218464/article/details/108987810