What is the result, when NULL is compared with NULL?

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What is the result, when NULL is compared with NULL?..

Answer / pravin

It is not possible to compare two nulls with each other.
Still if we want to compare null then we have isnull
operator.

Is This Answer Correct ?    4 Yes 5 No

What is the result, when NULL is compared with NULL?..

Answer / 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/

Is This Answer Correct ?    1 Yes 2 No

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