MySQL: SUM() with JOIN returns incorrect values

Question

I am trying to fetch a SUM() for each user in a table, but MySQL is returning the wrong values.

This is how it should look (http://sqlfiddle.com/#!2/7b988/4/0)

Answer 1

This is a old post , but i think this can help others

use distinct inside sum

SELECT 
    blocks.user_id, 
    SUM(distinct payout_history.amount) as amount
FROM blocks
LEFT JOIN payout_history
ON blocks.user_id = payout_history.user_id
WHERE confirms > 520
GROUP BY blocks.user_id

Refer this answer by @jerome wagner

MYSQL sum() for distinct rows