"CASE" statement within "WHERE" clause in SQL Server 2008 - sql

Question

I am working with a query which contains "CASE" statement within "WHERE" clause. But SQL Server 2008 is giving some errors while executing it. Can anyone please help me with the correct query? Here is the query:
SELECT
tl.storenum 'Store #',
co.ccnum 'FuelFirst Card #',
co.dtentered 'Date Entered',
CASE st.reasonid
WHEN 1 THEN 'Active'
WHEN 2 THEN 'Not Active'
WHEN 0 THEN st.ccstatustypename
ELSE 'Unknown'
END 'Status',
CASE st.ccstatustypename
WHEN 'Active' THEN ' '
WHEN 'Not Active' THEN ' '
ELSE st.ccstatustypename
END 'Reason',
UPPER(REPLACE(REPLACE(co.personentered,'RT\\\\',''),'RACETRAC\\\\','')) 'Person Entered',
co.comments 'Comments or Notes'
FROM
comments co
INNER JOIN cards cc ON co.ccnum=cc.ccnum
INNER JOIN customerinfo ci ON cc.customerinfoid=ci.customerinfoid
INNER JOIN ccstatustype st ON st.ccstatustypeid=cc.ccstatustypeid
INNER JOIN customerstatus cs ON cs.customerstatuscd=ci.customerstatuscd
INNER JOIN transactionlog tl ON tl.transactionlogid=co.transactionlogid
LEFT JOIN stores s ON s.StoreNum = tl.StoreNum
WHERE
CASE LEN('TestPerson')
WHEN 0 THEN co.personentered = co.personentered
ELSE co.personentered LIKE '%TestPerson'
END
AND cc.ccnum = CASE LEN('TestFFNum')
WHEN 0 THEN cc.ccnum
ELSE 'TestFFNum'
END
AND CASE LEN('2011-01-09 11:56:29.327')
WHEN 0 THEN co.DTEntered = co.DTEntered
ELSE
CASE LEN('2012-01-09 11:56:29.327')
WHEN 0 THEN co.DTEntered >= '2011-01-09 11:56:29.327'
ELSE co.DTEntered BETWEEN '2011-01-09 11:56:29.327' AND '2012-01-09 11:56:29.327'
END
END
AND tl.storenum < 699
ORDER BY tl.StoreNum

Answer 1

First off, the CASE statement must be part of the expression, not the expression itself.
In other words, you can have:
WHERE co.DTEntered = CASE
WHEN LEN('blah') = 0
THEN co.DTEntered
ELSE '2011-01-01'
END
But it won't work the way you have written them eg:
WHERE
CASE LEN('TestPerson')
WHEN 0 THEN co.personentered = co.personentered
ELSE co.personentered LIKE '%TestPerson'
END
You may have better luck using combined OR statements like this:
WHERE (
(LEN('TestPerson') = 0
AND co.personentered = co.personentered
)
OR
(LEN('TestPerson') <> 0
AND co.personentered LIKE '%TestPerson')
)
Although, either way I'm not sure how great of a query plan you'll get. These types of shenanigans in a WHERE clause will often prevent the query optimizer from utilizing indexes.

Answer 2

Try the following:
SELECT * FROM emp_master
WHERE emp_last_name=
CASE emp_first_name
WHEN 'test' THEN 'test'
WHEN 'Mr name' THEN 'name'
END

Answer 3

This should solve your problem for the time being but I must remind you it isn't a good approach :
WHERE
CASE LEN('TestPerson')
WHEN 0 THEN
CASE WHEN co.personentered = co.personentered THEN 1 ELSE 0 END
ELSE
CASE WHEN co.personentered LIKE '%TestPerson' THEN 1 ELSE 0 END
END = 1
AND cc.ccnum = CASE LEN('TestFFNum')
WHEN 0 THEN cc.ccnum
ELSE 'TestFFNum'
END
AND CASE LEN('2011-01-09 11:56:29.327')
WHEN 0 THEN CASE WHEN co.DTEntered = co.DTEntered THEN 1 ELSE 0 END
ELSE
CASE LEN('2012-01-09 11:56:29.327')
WHEN 0 THEN
CASE WHEN co.DTEntered >= '2011-01-09 11:56:29.327' THEN 1 ELSE 0 END
ELSE
CASE WHEN co.DTEntered BETWEEN '2011-01-09 11:56:29.327'
AND '2012-01-09 11:56:29.327'
THEN 1 ELSE 0 END
END
END = 1
AND tl.storenum < 699

Answer 4

I think that the beginning of your query should look like that:
SELECT
tl.storenum [Store #],
co.ccnum [FuelFirst Card #],
co.dtentered [Date Entered],
CASE st.reasonid
WHEN 1 THEN 'Active'
WHEN 2 THEN 'Not Active'
WHEN 0 THEN st.ccstatustypename
ELSE 'Unknown'
END [Status],
CASE st.ccstatustypename
WHEN 'Active' THEN ' '
WHEN 'Not Active' THEN ' '
ELSE st.ccstatustypename
END [Reason],
UPPER(REPLACE(REPLACE(co.personentered,'RT\\\\',''),'RACETRAC\\\\','')) [Person Entered],
co.comments [Comments or Notes]
FROM comments co
INNER JOIN cards cc ON co.ccnum=cc.ccnum
INNER JOIN customerinfo ci ON cc.customerinfoid=ci.customerinfoid
INNER JOIN ccstatustype st ON st.ccstatustypeid=cc.ccstatustypeid
INNER JOIN customerstatus cs ON cs.customerstatuscd=ci.customerstatuscd
INNER JOIN transactionlog tl ON tl.transactionlogid=co.transactionlogid
LEFT JOIN stores s ON s.StoreNum = tl.StoreNum
WHERE
CASE
WHEN (LEN([TestPerson]) = 0 AND co.personentered = co.personentered) OR (LEN([TestPerson]) <> 0 AND co.personentered LIKE '%'+TestPerson) THEN 1
ELSE 0
END = 1
AND
BUT
what is in the tail is completely not understandable

Answer 5

There WHERE part could be written like this:
WHERE
(LEN('TestPerson') <> 0 OR co.personentered = co.personentered) AND
(LEN('TestPerson') = 0 OR co.personentered LIKE '%TestPerson') AND
(cc.ccnum = CASE LEN('TestFFNum')
WHEN 0 THEN cc.ccnum
ELSE 'TestFFNum'
END ) AND
(LEN('2011-01-09 11:56:29.327') <> 0 OR co.DTEntered = co.DTEntered ) AND
((LEN('2011-01-09 11:56:29.327') = 0 AND LEN('2012-01-09 11:56:29.327') <> 0) OR co.DTEntered >= '2011-01-09 11:56:29.327' ) AND
((LEN('2011-01-09 11:56:29.327') = 0 AND LEN('2012-01-09 11:56:29.327') = 0) OR co.DTEntered BETWEEN '2011-01-09 11:56:29.327' AND '2012-01-09 11:56:29.327' ) AND
tl.storenum < 699

Answer 6

select
d.DISTNAME,e.BLKNAME,a.childid,a.studyingclass
from Tbl_AdmissionRegister a
inner join District_master b on a.Schooid=b.Schooid
where
case when len('3601')=4 then c.distcd
when len('3601')=6 then c.blkcd
when len('3601')=11 then c.schcd end = '3601'

Answer 7

Thanks for this question, actually I am looking for something else which is in below query. this may helps someone.
SELECT DISTINCT CASE WHEN OPPORTUNITY='' THEN '(BLANK)' ELSE OPPORTUNITY END
AS OPP,LEN(OPPORTUNITY) FROM [DBO].[TBL]
above query is to fill in dropdown which blank values shows as "(blank)". Also if we pass this value into sql where clause to get blank values with other values I don't know how to handle that. And finally came up with below solution this may helps to somebody.
here it is ,
DECLARE #OPP TABLE (OPP VARCHAR(100))
INSERT INTO #OPP VALUES('(BLANK)'),('UNFUNDED'),('FUNDED/NOT COMMITTED')
SELECT DISTINCT [OPPORTUNITY]
FROM [DBO].[TBL] WHERE ( CASE WHEN OPPORTUNITY ='' THEN '(BLANK)' ELSE OPPORTUNITY END IN (SELECT OPP FROM #OPP))
ORDER BY 1

Answer 8

You could also try like below eg. to show only Outbound Shipments
SELECT shp_awb_no,shpr_ctry_cd, recvr_ctry_cd,
CASE WHEN shpr_ctry_cd = record_ctry_cd
THEN "O"
ELSE "I"
END AS route
FROM shipment_details
WHERE record_ctry_cd = "JP"
AND "O" = CASE WHEN shpr_ctry_cd = record_ctry_cd
THEN "O"
ELSE "I"
END

Answer 9

CASE LEN('TestPerson')
WHEN 0 THEN co.personentered = co.personentered ELSE co.personentered LIKE '%TestPerson'
Try the following:
... and (
(LEN('TestPerson') = 0 and co.personentered = co.personentered) or
(LEN('TestPerson') <> 0 and co.personentered LIKE '%TestPerson') ) and ...

Answer 10

here is my solution
AND CLI.PE_NOM Like '%' + ISNULL(#NomClient, CLI.PE_NOM) + '%'
Regads
Davy

Answer 11

This works
declare #v int=A
select * from Table_Name where XYZ=202
and
dbkey=(case #v when A then 'Some Value 1'
else 'Some Value 2'
end)

Answer 12

I'm using somtehing like that to filter users according to needle as string and a dropdown in the UI
where
u.username like '%' + isnull(#needle, '') + '%'
and 1 =
(
case
when #status = 0 then 1 -- All in uu
when #status = u.statusid then 1 -- Special status
else 0 -- otherwise reject
end
)

Answer 13

select TUM1.userid,TUM1.first_name + ' ' +TUM1.last_name as NAME,tum1.Business_Title,TUM1.manager_id,tum2.First_Name + ' ' + tum2.Last_Name as [MANAGER NAME],TUM1.project,TUM1.project_code,TUM1.rcc_code,TUM1.department,TCM.Company_Name,
case
when tum1.Gender_ID=1 then 'male'
else 'female'
end 'GENDER'
,tum1.Band as BAND,
case when tum1.Inactive=0 then 'STILL IN COMPANY'
else 'LEFT COMPANY'
end 'ACTIVE/INACTIVE'
from tbl_user_master TUM1
join tbl_Company_Master TCM on TCM.Company_Code=TUM1.Company_Code
join tbl_User_Master TUM2 on TUM1.Manager_ID=TUM2.UserID
where tum1.UserID in ('54545414')

Answer 14

SELECT * from TABLE
WHERE 1 = CASE when TABLE.col = 100 then 1
when TABLE.col = 200 then 2 else 3 END
and TABLE.col2 = 'myname';
Use in this way.