SQL Select Case

Posted on 2013-05-22
Last Modified: 2013-06-04
I have a Select statement that returns user messages, please see code below.
As you see I (try to) use a Select Case method to set correct values to "DeletedId" and "DeletedOut". What I want to do is this:

1. If [To]=@To then DeletedId must be 0, else DeletedId can be 0 or 1 (doesn't matter).
2. If [From]=@From then DeletedOut must be 0, else DeletedOut can be 0 or 1 (doesn't matter).

SELECT Id, [From], [To] FROM tblUserMessage
WHERE ([To] = @To OR [From] = @From) AND (SiteId = @SiteId) AND (Deleted = '0') AND DeletedIn = (Case when [To] = @To Then '0' else '[0 or 1]' END) AND DeletedOut = (Case when [From] = @From Then '0' else '[0 or 1]' END)

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Hope someone please can help :)
Question by:webressurs
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Expert Comment

by:Ross Turner
ID: 39187185
I would do you case statement on a select within a select e.g

where field = field then 'something'
else 'other'
End as [Field]
from [YourTable]

) as Temp

where <inset your variables here>

Expert Comment

by:Ross Turner
ID: 39187213
i've created this example to give you a better idea of what i'm talking about!3/fc87a/3

Author Comment

ID: 39187329
Thanks for your reply RossTurner!
I did not fully understand your example, hope is it possible to get some help with my code below.

SELECT Id, [From], [To] FROM tblUserMessage
WHERE ([To] = 'jason' OR [From] = 'jason') AND (SiteId = '2') AND (Deleted = '0') AND DeletedIn = (Case when [To] = 'jason' Then '0' else '[DONT CARE]' END) AND DeletedOut = (Case when [From] = 'jason' Then '0' else '[DONT CARE]' END)            

Thanks :)
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Accepted Solution

webressurs earned 0 total points
ID: 39187348
I guess this is the solution I'm looking for?

SELECT Id, [From], [To] FROM tblUserMessage
WHERE ([To] = 'jason' OR [From] = 'jason') AND (SiteId = '2') AND (Deleted = '0') AND DeletedIn = (Case when [To] = 'jason' Then '0' else DeletedIn END) AND DeletedOut = (Case when [From] = 'jason' Then '0' else DeletedOut END)
LVL 69

Expert Comment

by:Scott Pletcher
ID: 39188390
SELECT Id, [From], [To]
FROM dbo.tblUserMessage
    ([To] = 'jason' OR [From] = 'jason') AND
    (SiteId = '2') AND
    (Deleted = '0') AND
    ([To] <> 'jason' OR DeletedIn = '0') AND
    ([From] <> 'jason' OR DeletedOut = '0')
LVL 41

Expert Comment

ID: 39189429
If you have data like this. Can you let us know which records you want? DO you want all of them?
To	From	DeletedIn	DeletedOut
jason	jason	0	0
jason	jason	1	0
jason	jason	0	1
jack	jason	0	0
jack	jason	1	0
jason	jack	0	0
jason	jack	0	1

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Author Closing Comment

ID: 39218373
This is the correct solution.

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