php - mysql 创建动态表

Question

我正在尝试动态创建一个表，我面临的唯一问题是动态创建列。我的意思是，我不会有固定数量的列，所以我尝试将其表示为变量，但是当我运行代码时，它给了我一个错误。以下是我尝试过的。

错误

You have an error in your SQL syntax; check the manual that corresponds to your...


$colArray = array();
foreach($ml as $df){
$colArray[] =  "`".$df."` VARCHAR(250) NOT NULL,<br/>";
}

$columns = implode("",$colArray);

$sql = "CREATE TABLE IF NOT EXISTS {$table_name}(
id INT NOT NULL AUTO_INCREMENT,
username VARCHAR(250) NOT NULL,
{$columns}
date VARCHAR(250) NOT NULL,
PRIMARY KEY (id)
            )";
 $stmt = $db->prepare($sql);
 echo $db->error;
 $stmt->execute();

Answer 1

这本质上应该是有效的:

$colArray = array();
// Since you want these two columns in order
// assign here
$colArray[] =  "id INT NOT NULL AUTO_INCREMENT";
$colArray[] =  "username VARCHAR(250) NOT NULL";

foreach($ml as $df) {
    $colArray[] =  "`".$df."` VARCHAR(250) NOT NULL";
}

// Since you want column last, assign here
$colArray[] =  "date VARCHAR(250) NOT NULL";

$columns = implode(",\r\n",$colArray);

$sql = "CREATE TABLE IF NOT EXISTS {$table_name}(
{$columns},
PRIMARY KEY (id))";
 $stmt = $db->prepare($sql);
 echo $db->error;
 $stmt->execute();