What's the best T-SQL syntax to filter for an ID that has a count of X or at least X or at most X in a joined table?
What's the best way to do something like this in T-SQL?
SELECT DISTINCT ID
FROM Members,
INNER JOIN Comments ON Members.MemberId = Comments.MemberId
开发者_JAVA技巧WHERE COUNT(Comments.CommentId) > 100
Trying to get the members who have commented more than 100 times. This is obviously invalid code but what's the best way to write this?
This should get you what you're after. I'm not saying this is the absolutely best way of doing it, but it's unlikely you'll find anything better.
SELECT ID
FROM Members
INNER JOIN Comments
ON Members.MemberId = Comments.MemberId
GROUP BY ID
HAVING COUNT(*) > 100
I like using a subquery.
SELECT DISTINCT m.ID
FROM Members m
WHERE (SELECT COUNT(c.CommentID)
FROM Comments c
WHERE c.MemberID = m.MemberID) > 100
Try
SELECT ID
FROM Members
INNER JOIN (SELECT MemberID FROM Comments
GROUP BY MemberID HAVING COUNT(CommentId) > 100)
AS CommentCount ON Members.MemberID = CommentCount.CommentID
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