I have a simple count query that can use Index Only Scan, but it still take so long in PostgresQL! I have a cars table with 2 columns type bigint and active boolean, I also have a multi-column ind...

In the following query SELECT col1,col2 FROM table1 WHERE col3='value1' AND col4='value2' If I have 2 separate indexes one on col3 and the other on col4, Which one of them will be used in this ...

I recently encountered an index in a database I maintain that was of the form: CREATE INDEX [IX_Foo] ON [Foo] ( Id ASC ) INCLUDE ( SubId ) In this particular case, the performance problem that ...