Cannot access temporary tables from within a function

Question

I would like to get count of specific records. So my query will look like the following...

SELECT
    ID, 
    NAME,
    (SELECT...) AS UserCount // Stmt1
FR         


        

Answer 1

I came across this post as I started using table variables and switched to temporary tables for performance reasons only to find temporary tables couldn't be used in a function.

I would be hesitant about using table variables especially if you are playing with large result sets, as these are held in memory. See this post...

http://totogamboa.com/2010/12/03/speed-matters-subquery-vs-table-variable-vs-temporary-table/

Other alternatives would be..

1. Extracting the temporary table result into another table function.
2. Converting the code into using sub-queries