Combining IN and NOT IN in SQL as single result
I apologize for the vague title. I am attempting to write a query that returns an alias column with matching va开发者_高级运维lues (resulting from an IN) as well as an alias column with values that do not match (using NOT IN). I want the result set to have: userId | matches | nonmatches. I currently have the following query which returns the matches as expected. I am having trouble getting the nonmatches in the result set -- that is, from a NOT IN statement
SET @userId = 9;
SELECT ug.user_id, COUNT(DISTINCT goal_id) as matches
FROM user_goal ug
WHERE ug.user_id!=@userId
AND goal_id IN (SELECT iug.goal_id FROM user_goal iug WHERE user_id=@userId)
GROUP BY user_id ORDER BY matches DESC LIMIT 4
So, the NOT IN would look something like this:
goal_id NOT IN(SELECT uggg.goal_id FROM user_goal uggg WHERE user_id=@userId) AS nonmatches
I am just not sure how to incorporate the NOT IN statement in my query so I get all the results
Try this (could be simplified and further optimized if mysql have CTE though):
select u.user_id, the_matches.matches, the_nonmatches.nonmatches
from user u
left join
(
SELECT ug.user_id, COUNT(DISTINCT goal_id) as matches
FROM user_goal ug
WHERE ug.user_id!=@userId
AND goal_id IN (SELECT iug.goal_id FROM user_goal iug WHERE user_id=@userId)
GROUP BY user_id
ORDER BY matches DESC LIMIT 4
) as the_matches on the_matches.user_id = u.user_id
left join
(
SELECT ug.user_id, COUNT(DISTINCT goal_id) as nonmatches
FROM user_goal ug
WHERE ug.user_id!=@userId
AND goal_id NOT IN(SELECT uggg.goal_id FROM user_goal uggg WHERE user_id=@userId)
GROUP BY user_id
) as the_nonmatches on the_nonmatches.user_id = u.user_id
group it by one another param, fix one param that will be used if there are goals from sub query
I think a UNION is what you need:
SET @userId = 9;
SELECT ug.user_id, COUNT(DISTINCT goal_id) as matches
FROM user_goal ug
WHERE ug.user_id!=@userId
AND goal_id IN (SELECT iug.goal_id FROM user_goal iug WHERE user_id=@userId)
GROUP BY user_id ORDER BY matches DESC LIMIT 4
union all
SELECT ug.user_id, COUNT(DISTINCT goal_id) as matches
FROM user_goal ug
WHERE ug.user_id!=@userId
AND goal_id NOT IN(SELECT uggg.goal_id FROM user_goal uggg WHERE user_id=@userId)
GROUP BY user_id ORDER BY matches DESC LIMIT 4
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