WHERE with wildcards

[CherylD]

I'm using a where clause that checks a description field, and selects where that description is NOT like something. For some reason, this excludes all records whose description field is null.

EG.
WHERE sysdba.SALESORDERDETAIL.DESCRIPTION NOT LIKE '%Membership%'

If description = "something", the row is returned.
If description = "1998 Membership fees", the row is not returned.
If description = &quot;<NULL>&quot;, the row is not returned.

What can I do to get the 3rd case(description = <NULL>) to return the row?

 

[sunila7]

hi,

u can add an or statemnet to ur SQL like this

WHERE (sysdba.SALESORDERDETAIL.DESCRIPTION NOT LIKE '%Membership%' or sysdba.SALESORDERDETAIL.DESCRIPTION is NULL)

Hope it helps

Sunil

 

[JamesLean]

The state of NULL is almost like a third boolean value ie, it is not True but is not False either - it is literally UNKNOWN.

Therefore to return NULL values in your query you need to do this:

WHERE column_name IS NOT LIKE '%membership%' OR column_name IS NULL

--James

 

[JamesLean]

Sorry - ignore the IS in the first statement:

WHERE column_name NOT LIKE '%membership%' OR column_name IS NULL

--James