How to populate a dataset in SSRS from a stored proc
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I'm creating a SSRS report from a stored procedure in SQL, when i add a dataset to the report i'm finding i'm having to add this to the top of my procedure in order for fields to be returned into my data set from the stored proc:

    IF 1=2 SELECT '' as [Date], '' as [Portfolio ID], '' as [Portfolio Base Ccy], 0 as [All in Market Value Base], 0 as [All in Market Value Converted]

Why would I have to do this and why does SSRS not simply pick up:

    SELECT [Date], [Portfolio ID],	 [Portfolio Base Ccy], [All in Market Value Base], [All in Market Value Converted]
    FROM @Worktable

from the bottom of my procedure or 

    SELECT * FROM @Worktable

?