Slow query on “UNION ALL” view

Question

I have a DB view which basically consists of two SELECT queries with UNION ALL, like this:

CREATE VIEW v AS
SELECT time, etc. FROM t1 /         


        

Answer 1

Combine the two tables. Add a column to indicate original table. If necessary, replace the original table names with views that select just the relevant part. Problem solved!

Looking into the superclass/subclass db design pattern could be of use to you.