Using multiple postgresql version with appropoiate psql and other pg tools version on mac with postgresapp
First make sure no postgres instance is configured to run on startup. And you get nothing when you run this command: which -a psql
This is to make sure you don't have anything related to postgres in your PATH, which can conflict.
If you do get some hits with above command, you have to manually either remove the installed versions of postgres or just fix PATH and remove ref to that path which has these binaries(psql, pg_dump etc)
For me, i was using brew installed postgres, i had to just comment out a PATH editing line which was inserted by brew in my .bash_profile
Ok, after this we are ready. Now things are simple: