Decrement a database table value if value >= 1 else... Delete the record

Question

I want to decrement a database table value if the field value is greater than or equal to 1 (>= 1). Otherwise (if it IS less than 1) then I want to delete that whole database record, My code decrements the value continuously but does not delete the record when it reaches less than 1.

I think the $Check variable does not hold the Quantity field value but I'm not sure:

Using MySQL

Here is my code:

$Check = "SELECT Quantity FROM Cart WHERE ItemCode = '1'";

if($Check >= '1')
{
    $Query = "UPDATE Cart SET Quantity = Quantity - 1 WHERE ItemCode = '1'";
    mysql_query($Query);
}
else
{
    $DeleteRow = "DELETE FROM Cart WHERE ItemCode = '1'";   
    mysql_query($DeleteRow);
}

mysql_close();

Answer 1

Try this piece of code:

<?php

    $Check = "SELECT Quantity FROM Cart WHERE ItemCode = '1'";
    $result = mysql_query($Check);

    $row = mysql_fetch_assoc($result);
    if($row['Quantity'] >= '1'){
    $Query = "UPDATE Cart SET Quantity = ".$row['Quantity']." - 1 WHERE ItemCode = '1'";

    mysql_query($Query);

    }
    else
    {
    $DeleteRow = "DELETE FROM Cart WHERE ItemCode = '1'";
    mysql_query($DeleteRow);
    }

    mysql_close();

?>

When you have this code running ok, try to adapting it to the mysqli extension on the procedural way; the mysql extension is deprecated.

It's not recommended the use of the mysql extension; you should try mysqli or PDO instead, follow this link and made your choice: http://www.phptherightway.com/#databases