How to fix pg_dump version mismatch errors?
When trying to get local data to Heroku, I am encountering a version mismatch between two different versions of pg_dump.
Specifically, I am getting this message:
pg_dump: server version: 9.2.2; pg_dump version: 9.1.4
pg_dump: aborting because of server version mismatch
I have found others with this problem, but do not know enough to implement the proposed solutions. (I am new to Ruby on Rails, PostgreSQL, Heroku, and the Mac! Very much at the stage of playing around the picking things up as I go.)
I was thinking I might simplify my life if I uninstalled all PostgreSQL on my local machine and started again with a clean install of PostgreSQL 9.2.2 from http://postgresapp.com/, but I don't know how to go about doing the uninstall.
I'm running Mac OS X Mountain Lion 10.8.2.
Answer
OS X 10.8 comes with pg_dump version 9.1.4 in the /usr/bin directory, along with psql and other programs that are client-side PostgreSQL tools. It does not mean that PostgreSQL as a server is installed (unless you have OS X Server Edition).
So you don't have to uninstall PostgreSQL because it's not installed and it's better not to remove these postgres client tools in /usr/bin because they belong to the system as shipped by Apple. They just need to be side-stepped.
The package provided by postgres.app comprises both the PostgreSQL server and the client-side tools of the same version as this server. These tools get installed in /Applications/Postgres.app/Contents/MacOS/bin
To use these instead of the 9.1 ones from Apple when you work in a Terminal, postgres.app documentation says to do:
PATH="/Applications/Postgres.app/Contents/MacOS/bin:$PATH"
and put it in your .profile file.
Once you have done that and you run pg_dump, you should no longer get the error that's it's the wrong version, because it would be the one that ships with postgres.app (currently 9.2.2).
I have this setup and it works OK for me.