Question

I’m stuck trying to remove the nested part from the following query :

    SELECT DISTINCT * FROM `audit` WHERE action_performed = 'REJECTED' AND `event_id` IN (
        SELECT DISTINCT event_id AS `Count` 
        FROM `audit` 
        WHERE username = 'someUser' 
        AND action_performed IN ('SUBMITTED_FOR_APPROVAL', 'SAVED_AND_APPROVED')
        AND (action_timestamp >= '2012-01-12 00:00:00' AND action_timestamp <= '2012-01-24 23:59:59'))

Basically, I’m trying to fetch the number of rejected events by a user, that were submitted by him before. I determine this by the action_performed column which takes values such as
SUBMITTED_FOR_APPROVAL, SAVED_AND_APPROVED and REJECTED.

The reason I want to remove the nested part is because the audit table currently contains over 100k rows, and the result of the nested query itself is around 2000 rows, so the query always times out.

I’ve tried searching on the site, and doing an INNER JOIN as suggested in some questions, but maybe I was doing it wrong!
Thank you.

EDIT – The audit table structure is as follows

Field              Type   
id                 int(11)
username           varchar(100)
event_id           int(11)
action_performed   varchar(100) 
action_timestamp   timestamp

Answer 1

SELECT DISTINCT adata.*
FROM  `audit` AS adata
INNER JOIN `audit` AS aselector ON adata.event_id=aselector.event_id
WHERE
  adata.action_performed = 'REJECTED'
  AND aselector.username = 'someUser' 
  AND aselector.action_performed IN ('SUBMITTED_FOR_APPROVAL', 'SAVED_AND_APPROVED')
  AND aselector.action_timestamp >= '2012-01-12 00:00:00'
  AND aselector.action_timestamp <= '2012-01-24 23:59:59'
;