How to check if column does not exist using PHP, PDO, MySQL?
mysql, pdo, php
Solution
I don't know if it helps you, but you can try this:
if (count($dbh->query("SHOW COLUMNS FROM `items` LIKE 'item_type'")->fetchAll())) {
$sth = $dbh->query ("SELECT item_type FROM items WHERE user_id = '$user_id'");
$row = $sth->fetch();
$item_type = $row['item_type'];
} else {
$item_type = null;
}
It checks if the column exists and performs the task.
Problem
In my application I have a generic query that applies to multiple users. There are instances where the table structure may differ between users. I have a query that I only want to apply to the users where the column exists in their table. ``` function get_item($user_id) { global $dbh; $sth = $dbh->query ("SELECT item_type FROM items WHERE user_id = '$user_id'"); $row = $sth->fetch(); $item_type = $row['item_type']; return $item_type; } ``` If the column 'item_type' does not exist in my table, I want to ignore it, and set the $item_type variable to NULL. For these users, I am getting the error on the query line of code: Fatal error: Uncaught exception 'PDOException' with message 'SQLSTATE[42S22]: Column not found: 1054 Unknown column 'item_type' in 'field list' in /item_display.php:5 Any ideas?