TimeTrex Time and Attendance

I have installed Timetrex v9.1.2 on a Windows 8.1 machine and used the automated executable installer.

I would like to run queries to the Postgress database.

How should I do this?

You should not run queries directly to the database due to the complexity of the database. You could very easily mess something up and render TimeTrex useless. You should use the TimeTrex API.