Using MySql workbench, assume an existing database design of a cloth store...

Add the necessary code to satisfy those conditions:

NOTE: YOUR CODE SHOULD BE ORIGINAL AND COMMENTS SHOULD BE PROVIDED FOR EVERY STEP

-purchased date to be stored, no returns are allowed exceeding 30 days from the purchase date.

-returns during the first 15 days after the purchase are free charged.

- returns after the first 15 days of the purchase to day number 30 are charged with 10% extra fees

-only cash purchases customers are allowed to return their purchases

- any customer is not allowed to check out with a purchase if he don't have zero balance.