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
353 views
in Technique[技术] by (71.8m points)

sql - Simple check for SELECT query empty result

Can anyone point out how to check if a select query returns non empty result set?

For example I have next query:

SELECT * FROM service s WHERE s.service_id = ?;

Should I do something like next:

ISNULL(SELECT * FROM service s WHERE s.service_id = ?)

to test if result set is not empty?

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)
IF EXISTS(SELECT * FROM service s WHERE s.service_id = ?)
 BEGIN
   --DO STUFF HERE

 END

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

...