<?php
    //1.验证mysqli扩展是否已经开启
    phpinfo();
    //2.检测扩展是否已经加载
    var_dump(extension_loaded('mysqli'));
    //开启返回true
    //3.检测函数是否存在
    var_dump(function_exsts('mydqli_connect'));
    //4.得到开启的扩展
    print_r(get_loaded_extensions());Copy

header('content-type:text/html;charset=utf-8');

$host = '127.0.0.1';
$user = 'root';
$password = 'root';
$db = 'test';

$link = mysqli_connect($host, $user, $password,$db) or die('connect error'.mysqli_connect_errno().":".mysqli_connect_error());
mysqli_set_charset($link,'utf8');//设置字符集，字符集区别

$username = 'seven';
$password = md5("seven");
$create_time = date('Y-m-d H:i:s');
$update_time = date('Y-m-d H:i:s');
//增加
$sql = "insert user(username, password, create_time, update_time) values('{$username}', '{$password}', '{$create_time}', '{$update_time}')";
$res = mysqli_query($link, $sql); //返回true or false
if($res){
    echo  '自增长id'.mysqli_insert_id($link);
    echo PHP_EOL;
    echo  '受影响的行数'.mysqli_affected_rows($link);
}else{
    echo 'error'.PHP_EOL.mysqli_errno($link).":".mysqli_error($link);
}Copy

<?php
    header('content-type:text/html;charset=utf-8');

    $host = '127.0.0.1';
    $user = 'root';
    $password = 'root';
    $db = 'test';

    $link = mysqli_connect($host, $user, $password,$db) or die('connect error'.mysqli_connect_errno().":".mysqli_connect_error());
    mysqli_set_charset($link,'utf8');//设置字符集，字符集区别

    $sql = 'delete from user where id = 1';
    $result = mysqli_query($sql);
    if($result && myslqi_num_rows($result)>0){
        while($row = mysqli_fetch_array($result, MYSQLI_ASSOC)){
            $rows[]=$row;
        }
    }
    //释放结果集
    mysqli_free_result($result);
    //关闭连接
    mysqli_close($link);Copy

<?php
    header('content-type:text/html;charset=utf-8');

    $host = '127.0.0.1';
    $user = 'root';
    $password = 'root';
    $db = 'test';

    $link = mysqli_connect($host, $user, $password,$db) or die('connect error'.mysqli_connect_errno().":".mysqli_connect_error());
    mysqli_set_charset($link,'utf8');//设置字符集，字符集区别

    $sql = 'select * from user';
    $result = mysqli_query($sql);
    if($result && myslqi_num_rows($result)>0){
        while($row = mysqli_fetch_array($result, MYSQLI_ASSOC)){
            $rows[]=$row;
        }
    }
    //释放结果集
    mysqli_free_result($result);
    //关闭连接
    mysqli_close($link);Copy

<?php
    header('content-type:text/html;charset=utf-8');
    $host = '127.0.0.1';
    $user = 'root';
    $password = 'root';
    $db = 'test';

    $link = mysqli_connect($host, $user, $password,$db) or die('connect error'.mysqli_connect_errno().":".mysqli_connect_error());
    mysqli_set_charset($link,'utf8');//设置字符集，字符集区别

    // 修改
    $sql = 'update user set age=age+10 where id=41';
    $res = mysqli_query($link,$sql); //执行多条sql语句
    if($res){
        echo  '自增长id'.mysqli_insert_id($link);
        echo PHP_EOL;
        echo  '受影响的行数'.mysqli_affected_rows($link);
    }else{
        echo 'error:<br/>';
        echo mysqli_errno($link),":".$mysqli_error($link);
    }
    //关闭连接
    mysqli_close($link);Copy