RE: Case Statement in Join condition

SSC Guru

Points: 186127

September 2, 2014 at 3:22 am

Indu-649576 (9/2/2014)
IS there any way I can use the below
Select X.* From TABLE X
INNER JOIN
(case when (condition) then TABLE A else TABLE B end) AS Y
ON X.Col1 = Y.Col1

Not literally, no - but there are numerous ways of obtaining the same logical result. Can you show the condition, as well as the joins between x and a, and x and y?

^{“Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw}

For fast, accurate and documented assistance in answering your questions, please read this article.
Understanding and using APPLY, (I) and (II) Paul White
Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden