php - 如何在 PHP 中为不同的表发送两个查询？

Question

我想在名为“preise”的表中创建新数据。如果我这样做，我想在名为“tische”的表中添加一列，其中包含我在“preise”中创建的数据的标题 我希望你能明白我的意思(我的英语不是很好”) 这是我的 PHP:

<?php 
    if($_SERVER['REQUEST_METHOD']=='POST'){

        //Getting values
        $name = $_POST['name'];
        $ebene = $_POST['ebene'];
        $preis = $_POST['preis'];

        //Creating an sql query
        $sql = "INSERT INTO preise (name,ebene,preis) VALUES ('$name','$ebene','$preis')";
    $add = "ALTER TABLE tische ADD COLUMN $name INT(5) NOT NULL AFTER id";

        //Importing our db connection script
        require_once('dbConnect.php');

        //Executing query to database
        if(mysqli_query($con,$sql,$add)){
            echo 'Element erfolgreich hinzugefügt';
        }else{
            echo 'Konnte Element nicht hinzufügen';
        }

        //Closing the database 
        mysqli_close($con);
    }

如果我删除 $add... 处的行，那么脚本将按原样执行 $sql。但是如何执行 $add 查询呢？

Answer 1

不同的查询应该分开执行。

一个简单的例子:

//Creating an sql query
$insert_query = "INSERT INTO preise (name,ebene,preis) VALUES ('$name','$ebene','$preis')";
$alter_query = "ALTER TABLE tische ADD COLUMN $name INT(5) NOT NULL AFTER id";

//Importing our db connection script
require_once('dbConnect.php');

//Executing query to database

// mysqli_query takes TWO or THREE arguments only
// and third argument is an INT value
// so passing another query as third argument is USELESS
if (mysqli_query($con, $insert_query)){

    // if first query is okay
    // we can run second one
    $r = mysqli_query($con, $alter_query);
    if ($r) {
        // both queries are OK
        echo 'Element erfolgreich hinzugefügt';
    } else {
        echo 'Some error message here';
    }
} else {
    echo 'Konnte Element nicht hinzufügen';
}

//Closing the database 
mysqli_close($con);

进一步阅读:

• > using prepared statements
• > using transactions
• > using multiquery