检查用户是为了满足MySQL的要求

Question

I'm making an web with point and reward system where user collect points and if users point meet the requirement, user will get a reward and level up.

As example, here's my user table

id | username | level | point
1  | nameuser | 0     | 0

Award :

idaward | awardname | pointreq | badgeid
1       | LEVEL ONE | 10       | 1

and so on, I have 100+ award for user.

Award log

idlog | userid | awardid | badgeid | givendate

And my purpose is how to check if user is eligible or meet the requirement to get an award & badge ?

The flow:

Users have a point -> check if user meets the requirement to level up & get award 
-> Users will leveled up and get a reward (insert the info. to award log)
    If users already have it then ignore it.

I'm using Laravel, so if you can make the Laravel query, I will really appreciate it but I will also accept raw MySQL query.

Thank you

Answer 1

You can execute the following update query:

UPDATE user
SET level = level + 1
WHERE
id = ?
AND EXISTS (
    SELECT * FROM award WHERE pointreq <= user.point 
    AND awardid NOT IN (
        SELECT awardid from awardlog WHERE userid = user.id
    )
);

If the update returns 1 then you need to insert an entry into awardlog table, you can use following SELECT and INSERT queries for it:

SELECT * FROM award WHERE pointreq <= user.point 
AND awardid NOT IN (
   SELECT awardid from awardlog WHERE userid = user.id
);

You can get awardid and badgeid from above query and insert into awardlog.

Also, you need to make sure all 3 queries ( UPDATE , SELECT and INSERT ) get executed in a single transaction for consistency.