mysql update table ajax by class

Question

i\'m trying to update rows quantity using ajax by class not id i have looked on google for hours trying to work this out but everything i could find didnt seem to work

m

Answer 1

1. Your code is vulnerable to SQL injection.

2. You're using a deprecated API which does not support prepared statements to prevent SQL injection

3. You can combine your UPDATE and SELECT into a single statement. Here's an idea

4. Your deduction should be database based, not value based

   UPDATE tbl UPDATE col = col - 1