UDF not returning the same value as select contained in UDF - sql

Question

I created this UDF
CREATE FUNCTION [dbo].[HasExtendedRetentionSamples] (#BoxNumber varchar(20))
RETURNS int
AS
BEGIN
declare #cnt int
set #cnt = 0
select #cnt = (select count(*)
from tFreezerBoxInfo bi
inner join tFreezerDetails fd on fd.boxTrayId = bi.boxTrayId
inner join tncDrugTestListNew dt on dt.labnumber = fd.labnumber
inner join ExtendedRetentionSites a on dt.number = a.number
where boxnumber = 'ND011811001'
and
case isnull([retention],0)
when 0 then proposedDestructionDate
else dateadd(dd,abs([retention]),proposedDestructionDate)
end <> proposedDestructionDate)
return #cnt
END
When I execute the UDF
select dbo.[HasExtendedRetentionSamples] ('ND011811001')
The value 0 is returned, which is incorrect,
When I execute the SQL statement contained in the UDF (replacing #BoxNumber with 'ND011811001')...
select count(*)
from tFreezerBoxInfo bi
inner join tFreezerDetails fd on fd.boxTrayId = bi.boxTrayId
inner join tncDrugTestListNew dt on dt.labnumber = fd.labnumber
inner join ExtendedRetentionSites a on dt.number = a.number
where boxnumber = 'ND011811001'
and
case isnull([retention],0)
when 0 then proposedDestructionDate
else dateadd(dd,abs([retention]),proposedDestructionDate)
end <> proposedDestructionDate
The value 5 is returned, which is correct.
So the big question is WHY????
All the datatype in the joins & case statement are the same.

Answer 1

I would change the function to this, take the count out of the subquery:
CREATE FUNCTION [dbo].[HasExtendedRetentionSamples] (#BoxNumber varchar(20))
RETURNS int
AS
BEGIN
declare #cnt int
set #cnt = 0
select #cnt = count(*)
from tFreezerBoxInfo bi
inner join tFreezerDetails fd on fd.boxTrayId = bi.boxTrayId
inner join tncDrugTestListNew dt on dt.labnumber = fd.labnumber
inner join ExtendedRetentionSites a on dt.number = a.number
where boxnumber = 'ND011811001'
and
case isnull([retention],0)
when 0 then proposedDestructionDate
else dateadd(dd,abs([retention]),proposedDestructionDate)
end <> proposedDestructionDate
return #cnt
END
try changing your CASE statement to:
case
when isnull([retention],0) = 0 then proposedDestructionDate
else dateadd(dd,abs([retention]),proposedDestructionDate)
end <> proposedDestructionDate

Answer 2

I am embarrassed to say, I have found out why this was happening.....
When I created the table ExtendedRetentionSites, it was created & populated with me as the owner. I realized that and recreated the table with DBO as the owner, populating this table, but never dropping the table with the same name that I owned. I ran an insert statement & it inserted into ExtendedRetentionSites that I owned, but this data never made it to the table that DBO owned.
Soooooo when I ran the select script, it used ExtendedRetentionSites that I owned, that had the new row, that would give me the results I was looking for. When I ran the UDF, it used the table that DBO owned, without the new row thus returning nothing or a zero count.
Thanks to everyone who helped me out with this, I will now pull my head out of my ass & get back to work.
Thanks again to all!!!!