CASE WHEN statement for ORDER BY clause
I am using SQL Server 2008 R2.
I want the priority based sorting for records in a table.
So that I am using CASE WHEN statement in ORDER BY clause. The ORDER BY clause is as below :
ORDER BY
CASE WHEN TblList.PinRequestCount <> 0 THEN TblList.PinRequestCount desc, TblList.LastName ASC, TblList.FirstName ASC, TblList.MiddleName ASC END,
CASE WHEN TblList.HighCallAlertCount <> 0 THEN TblList.HighCallAlertCount desc, TblList.LastName ASC, TblList.FirstName ASC, TblList.MiddleName ASC END,
Case WHEN TblList.HighAlertCount <> 0 THEN TblList.HighAlertCount DESC, TblList.LastName ASC, TblList.FirstName ASC, TblList.MiddleName ASC END,
CASE WHEN TblList.MediumCallAlertCount <> 0 THEN TblList.MediumCallAlertCount DESC, TblList.LastName ASC, TblList.FirstName ASC, TblList.MiddleName ASC END,
Case WHEN TblList.MediumAlertCount <> 0 THEN TblList.MediumAlertCount DESC, TblList.LastName ASC, TblList.FirstName ASC, Patlist.MiddleName ASC END
But it gives Incorrect syntax near the keyword 'desc'
Any solution?
Also I can have:
TblList.PinRequestCount <> 0 and TblList.HighCallAlertCount <> 0 and
TblList.HighAlertCount <> 0` and TblList.MediumCallAlertCount <> 0 and
TblList.MediumAlertCount <> 0
at the same time.
Solution 1:
CASE
is an expression - it returns a single scalar value (per row). It can't return a complex part of the parse tree of something else, like an ORDER BY
clause of a SELECT
statement.
It looks like you just need:
ORDER BY
CASE WHEN TblList.PinRequestCount <> 0 THEN TblList.PinRequestCount END desc,
CASE WHEN TblList.HighCallAlertCount <> 0 THEN TblList.HighCallAlertCount END desc,
Case WHEN TblList.HighAlertCount <> 0 THEN TblList.HighAlertCount END DESC,
CASE WHEN TblList.MediumCallAlertCount <> 0 THEN TblList.MediumCallAlertCount END DESC,
Case WHEN TblList.MediumAlertCount <> 0 THEN TblList.MediumAlertCount END DESC,
TblList.LastName ASC, TblList.FirstName ASC, TblList.MiddleName ASC
Or possibly:
ORDER BY
CASE
WHEN TblList.PinRequestCount <> 0 THEN TblList.PinRequestCount
WHEN TblList.HighCallAlertCount <> 0 THEN TblList.HighCallAlertCount
WHEN TblList.HighAlertCount <> 0 THEN TblList.HighAlertCount
WHEN TblList.MediumCallAlertCount <> 0 THEN TblList.MediumCallAlertCount
WHEN TblList.MediumAlertCount <> 0 THEN TblList.MediumAlertCount
END desc,
TblList.LastName ASC, TblList.FirstName ASC, TblList.MiddleName ASC
It's a little tricky to tell which of the above (or something else) is what you're looking for because you've a) not explained what actual sort order you're trying to achieve, and b) not supplied any sample data and expected results, from which we could attempt to deduce the actual sort order you're trying to achieve.
This may be the answer we're looking for:
ORDER BY
CASE
WHEN TblList.PinRequestCount <> 0 THEN 5
WHEN TblList.HighCallAlertCount <> 0 THEN 4
WHEN TblList.HighAlertCount <> 0 THEN 3
WHEN TblList.MediumCallAlertCount <> 0 THEN 2
WHEN TblList.MediumAlertCount <> 0 THEN 1
END desc,
CASE
WHEN TblList.PinRequestCount <> 0 THEN TblList.PinRequestCount
WHEN TblList.HighCallAlertCount <> 0 THEN TblList.HighCallAlertCount
WHEN TblList.HighAlertCount <> 0 THEN TblList.HighAlertCount
WHEN TblList.MediumCallAlertCount <> 0 THEN TblList.MediumCallAlertCount
WHEN TblList.MediumAlertCount <> 0 THEN TblList.MediumAlertCount
END desc,
TblList.LastName ASC, TblList.FirstName ASC, TblList.MiddleName ASC
Solution 2:
Another simple example from here..
SELECT * FROM dbo.Employee
ORDER BY
CASE WHEN Gender='Male' THEN EmployeeName END Desc,
CASE WHEN Gender='Female' THEN Country END ASC