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tsql NULL record not showing with CASE

My query is not showing my NULL values.  What am I missing?  Thanks!

SELECT        AccessList.ALMYID, AccessList.FirstName, AccessList.LastName, AccessList.ClassStanding, Seminars.SeminarDetails, AccessList.TermGPA, 
                         AccessList.MYCompletedCredits, StudentSeminars.SHasAttended, StudentSeminars.SSeminarID, AccessList.CumulativeGPA, AccessList.CompletedCredits, 
                         AccessList.IsTransfer, Demographics.DEmail, 
						 CASE WHEN (StudentSignature.SSigID IS NULL) 
						 THEN 'No'
						 ELSE 'Yes'
						 END AS Signed
FROM            AccessList INNER JOIN
                         StudentSeminars ON AccessList.ALMYID = StudentSeminars.SMYID INNER JOIN
                         Seminars ON StudentSeminars.SSeminarSelected = Seminars.SeminarID INNER JOIN
                         Demographics ON StudentSeminars.SMYID = Demographics.DMYID INNER JOIN
                         StudentSignature ON StudentSeminars.SMYID = StudentSignature.SSMYID
WHERE (Seminars.SeminarID = @SeminarID)

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2 Solutions
Dale BurrellDirectorCommented:
What values are null? And how do you know?

Best guess is because all your joins are inner joins which means that any rows joined on null will mean the entire row doesn't show. You need to use left joins if you want to see null values.
HuaMinChenBusiness AnalystCommented:
Put a relevant value for Null column, like

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If there is no corresponding record at all in the StudentSignature table then you need to use LEFT OUTER JOIN for it instead of INNER JOIN.  This is what I suspect since your CASE statement is phrased correctly for NULL in that field.
javierpdxAuthor Commented:
Thanks. With LEFT JOIN, the No value did show as "No".
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