I was wondering if anyone could shed any light on this. I am using SQL Server
I start with 1 view (VIEW A) that uses a UNION statement that includes 2
queries. Each query is not too complicated (i.e. few joins but no subquery).
I then run a report and it take a long time to run.
So I decide to make 2 new views each with one query. Then I modify the
original view (VIEW A) to use a UNION statement that combines the 2 views,
rather than the queries.
This runs much faster.
I am surprised by this. Should I be? I have never been a fan of views of
view because of the admin nightmare of too many views. But it seems like
there is a performance advantage. Can this be true?