Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Welcome To Ask or Share your Answers For Others

Categories

0 votes
340 views
in Technique[技术] by (71.8m points)

sql - Possible to do a delete with a HAVING clause?

I want to do something like below:

DELETE UserPredictions
  GROUP BY UserId
  HAVING COUNT(*) < 500

But I'm getting a syntax error. Is it even possible to do a delete with a HAVING clause in SQL Server or will I have to roll the counts up into a CTE and do a delete with a join?

See Question&Answers more detail:os

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
Welcome To Ask or Share your Answers For Others

1 Reply

0 votes
by (71.8m points)

Not really. The having clause implies an aggregation, which means you don't have the original rows any more.

I think you want the following:

DELETE from UserPredictions
where UserId in (select UserId from UserPredictions group by UserId having count(*) < 500)

与恶龙缠斗过久,自身亦成为恶龙;凝视深渊过久,深渊将回以凝视…
OGeek|极客中国-欢迎来到极客的世界,一个免费开放的程序员编程交流平台!开放,进步,分享!让技术改变生活,让极客改变未来! Welcome to OGeek Q&A Community for programmer and developer-Open, Learning and Share
Click Here to Ask a Question

...