Re: Optimize complex query with arithmetic calculations

[Craig Matthews]

Thanks for your thoughts.

I am wondering if every website that runs MySQL has indexes like in your example, which is what my DB looks like now!

So assuming I have 4 columns in the most-accessed main table, I have a variety of permutations of WHERE conditions:

where col1 = xyz
where col2 = xyz
where col3 = xyz
where col4 = xyz
where col1 = xyz and col3 = abc
where col2 = xyz and col3 = abc
..etc

So for each of these situations, is it customary to have an individual index on the columns, and then composite indexes?