How do I use a comma separated list of values as a filter in T-SQL?

Question

I have a basic SQL query, starting with:

SELECT top 20 application_id, [name], location_id FROM apps

Now, I would like to finish it so that it

Answer 1

If @locid is a list eg "33, 234" etc, then no solution here will work. However, I guess these were posted before your update with this information.

I assume that because you said this:

@locid is the results given by the user, for example '33, 234'

You can not expand the variable directly so that location_in IN (33, 234). You are actually asking for location_id = '33, 234', which will fail with a CAST conversion, because of datatype precedence.

You have to parse the list first into a table form for use in a JOIN/EXISTS construct. There are several options and Erland covers them all here: Arrays and Lists in SQL Server 2005

Answer 2

WHERE CHARINDEX(LocationId, @lid) > 1

Answer 3

You don't really need the ternary operator for this:

SELECT top 20 application_id, [name], location_id
FROM apps
WHERE (@lid > 0 AND location_id IN (@lid)) OR @lid <= 0

Answer 4

The following should do the trick for you.

DECLARE @lid SMALLINT

SET @lid = 0

SELECT top 20 application_id, [name], location_id

FROM apps

WHERE ((@lid > 0 AND location_id = @lid)

  OR (@lid = 0 AND location_id > @lid))

If @lid = 0 then it will return ALL rows. IF @lid has a particular value, only the row for that @lid value is returned.