PHP 操作 mysql 预处理

由于本地 PHP 版本过底,没办法进行完整的测试

$host = 'localhost';
$user = 'root';
$password = '';
$dbname = 'cmstop';
$mysqli = new mysqli($host, $user, $password, $dbname) or exit('无法连接到mysql:'.$mysqli->connect_error);

 $sql  = "SELECT CURRENT_USER(); SELECT * FROM `db_setting` LIMIT 5;";

if ($mysqli->multi_query($sql)){//多条查询
    do{
        if($result = $mysqli->store_result()){//如果还有还结果集,取当前的一个结果集返回
            while($row = $result->fetch_row()){//取一条记录
                echo $row[0];
            }
            $result->free();//当此结果集中无记录时,释放
        }
        if($mysqli->more_results()){//如果还有一个结果集,则输出分隔线
            echo "<hr />";
        }
    }while($mysqli->next_result());
} 


//预处理
$sql = "SELECT `app`,`var` FROM `db_setting` WHERE `app`=? LIMIT 5";
$app = 'article';
$stmt = $mysqli->stmt_init();
if($stmt->prepare($sql)) {
    $stmt->bind_param("s", $app);
    $stmt->execute();//执行查询
    
    $stmt->bind_result($field1, $field2); //生成两个字段的结果集
    while ($stmt->fetch()) {
        echo '<br/>', $field1,' => ', $field2;
    }
    echo'<hr/>';
    
    $app = 'guestbook';
    $stmt->execute();//执行查询
    $result = $stmt->get_result(); //生成两个字段的结果集
    while ($row = $result->fetch_array(MYSQLI_NUM)){
        echo $row[0],' => ',$row[1];
    }
    
    $stmt->close();
}
$mysqli->close();