Answer Posted / gaurav arora

The answer-6 is quite matching with my stuff. Let me clear
it in more writting:
1. When we compare two nulls then the result
always 'false'. The main reason is the null is not a value
its neither an empty nor a empty space, so the actual
result is null which places as null.
2. When we compare a null with another which has some value
like some int value then the result is false. The actual
result is false and not null.

Consider the following examples:

--null = null is null which is false
Declare @intNull1 int
Set @intNull1 =null
Declare @intNull2 int
Set @intNull2=null
If @intNull1=@intNull2
Print 'null = null is true'
Else
Print 'null = null is false'

--Now assign some value
Set @intNull1 = 1
If @intNull1=@intNull2
Print 'null = int value is true'
Else
Print 'null = int value is false'

Thanks,
Gaurav Arora
http://stuff4mdesktop.blogspot.com/

how to delete duplicate rows from a join tables(I have three tables on that join) how do you know which join is need to be used? The select statement I have is: SELECT gc_skill_type.skill_type, gc_area_tec.area, gc_technology.technology, gc_technology.id_technology, gc_area_tec.id_area_tec FROM gc_skill_type, gc_area_tec, gc_technology WHERE gc_area_tec.id_skill_type (+) = gc_skill_type.id_skill_type AND gc_technology.id_area_tec (+) = gc_area_tec.id_area_tec order by gc_skill_type.skill_type asc, gc_area_tec.area asc, gc_technology.technology asc

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