MySQL RateModel(cid, m, r)

Question

Write a stored procedure RateModel(cid, m, r) which inserts a new rating r for model m by customer cid into table ratings.

The rating_time should be the current date and time.
This procedure allows rating NULL to be inserted only if the previous rating of model m by cid is not NULL.
This procedure also updates the discount for this cid in table customers as follows. If a customer has rated 5 or more products (counting only non-NULL current ratings) and their discount in table customers is less than 10.0 then change their discount in table customers to 10.0.

Answer 1

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