在MySQL中添加列數作爲標題的總列數

Question

如何在名爲「tische」的表格中添加一個新列，並在該表格中列標題的列標題？ 我嘗試以下codem但是，這並不工作...

<?php 

//Creating an sql query 
$number = "SELECT COUNT(*) FROM INFORMATION_SCHEMA.COLUMNS WHERE table_name = 'tische'"; 
$rs  = mysqli_query($number); 
$result = mysqli_fetch_array($rs); 
$add = "ALTER TABLE tische ADD COLUMN `$result` VARCHAR(100) NOT NULL AFTER zeit"; 

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

//Executing query to database 
if (mysqli_query($con, $add)) { 
    echo 'Element erfolgreich hinzugefügt'; 
} else { 
    echo 'Fehler!'; 
} 
//Closing the database 
mysqli_close($con); 

當我在phpMyAdmin的控制檯執行querys，它的工作原理。但不是在這個PHP腳本...請幫助我

Answer 1

在頁面頂部添加require_once('dbConnect.php');。在mysqli_query第一個參數添加$con可變像$rs = mysqli_query($con, $number);

SYNTAX mysqli_query的：

mysqli_query(mysqli $con , string $query [, int $resultmode = MYSQLI_STORE_RESULT ])

你的校正碼是波紋管：

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

    //Creating an sql query 
    $number = "SELECT COUNT(*) as total FROM INFORMATION_SCHEMA.COLUMNS WHERE table_name = 'tische'"; 
    $rs = mysqli_query($con, $number); 

    $column_name = 0; 
    if(mysqli_num_rows($rs) > 0) { 
     while($result = mysqli_fetch_array($rs)) { 
      $column_name = $result['total']; 
     } 

     $add = "ALTER TABLE tische ADD COLUMN `$column_name` VARCHAR(100) NOT NULL AFTER zeit"; 

     //Executing query to database 
     if(mysqli_query($con,$add)){ 
     echo 'Element erfolgreich hinzugefügt'; 
     } else { 
     echo 'Fehler!'; 
     } 
    } 
    //Closing the database 
    mysqli_close($con); 
?>