Please start any new threads on our new
site at https://forums.sqlteam.com. We've got lots of great SQL Server
experts to answer whatever question you can come up with.
| Author |
Topic |
|
Hammerklavier
Starting Member
26 Posts |
 Posted - 2015-03-10 : 09:37:04
|
| Hi,I have heard it is a performance hit to use the "not equal to" operator in a where clause, like this:SELECT * FROM MyTable WHERE TypeID <> 11If you want everything except for TypeID of 11, what is the preferred way of handling such a query?Thank you! |
|
|
gbritton
Master Smack Fu Yak Hacker
2780 Posts |
Posted - 2015-03-10 : 10:17:46
|
| you heard wrong. However, when you think about it, the only way Sql can satisfy your query is with an index scan (if TypeId is indexed) or a table scan (If Typeid is NOT indexed). It will be better if TypeID is indexed, though |
 |
|
|
magbenyezi
Starting Member
3 Posts |
Posted - 2015-03-11 : 11:41:22
|
| SELECT * FROM MyTable t WHERE t.TypeID NOT IN (SELECT t1.TypeID FROM MyTable t1 WHERE t1.TypeID = 11 )MA |
|
|
|
tkizer
Almighty SQL Goddess
38200 Posts |
Posted - 2015-03-11 : 11:56:36
|
quote:
Originally posted by magbenyezi
SELECT * FROM MyTable t WHERE t.TypeID NOT IN (SELECT t1.TypeID FROM MyTable t1 WHERE t1.TypeID = 11 )MA
Good grief, just no.Tara KizerSQL Server MVP since 2007http://weblogs.sqlteam.com/tarad/ |
|
|
|
gbritton
Master Smack Fu Yak Hacker
2780 Posts |
Posted - 2015-03-11 : 12:09:51
|
| @tkizer LOL! |
|
|
|
tkizer
Almighty SQL Goddess
38200 Posts |
Posted - 2015-03-11 : 12:11:40
|
| Gerald, I tried replying to your email from like 3 weeks ago, but it bounced back. Just FYI.Tara KizerSQL Server MVP since 2007http://weblogs.sqlteam.com/tarad/ |
|
|
|
gbritton
Master Smack Fu Yak Hacker
2780 Posts |
Posted - 2015-03-11 : 12:19:05
|
| @tkizer thanks. I'll check my profile (and fix it!) |
|
|
|
|
|
|
Alternative to using "<>" in WHERE clause