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 |
|
nismo
Starting Member
3 Posts |
 Posted - 2008-04-29 : 23:11:19
|
| Select * from table where field <> 'This'Why does that not return nulls? 'This' does not equal null. Why does sql server work this way? |
|
|
SwePeso
Patron Saint of Lost Yaks
30421 Posts |
Posted - 2008-04-30 : 02:30:47
|
NULL means unknown value.And since you are SELECTing all records where Field is not equal to "This" NULL obviously can't be fetched, because you don't know their values. It is unknown, or a better word "undetermined".Select * from table where coalesc(field, 'x') <> 'This'
E 12°55'05.25"N 56°04'39.16" |
 |
|
|
visakh16
Very Important crosS Applying yaK Herder
52326 Posts |
Posted - 2008-04-30 : 03:02:25
|
quote:
Originally posted by nismo
Select * from table where field <> 'This'Why does that not return nulls? 'This' does not equal null. Why does sql server work this way?
NULL is not stored as a value. Its actually set as an internal bit to indicate unknown value. So it wont be fetched using above condition. |
|
|
|
|
|
|
Why are nulls not being returned?