Unpivot

In my previous post about unpivot in Postgres I showed how this can be done in a compact manner without using a series of UNION statements.

But Postgres offers an even more compact and dynamic way to do this.

Sometimes it’s necessary to normalize de-normalized tables - the opposite of a “crosstab” or “pivot” operation. Postgres does not support an UNPIVOT operator like Oracle or SQL Server, but simulating it, is very simple.