If you learn right, you may learn to love SQL - well I do anyway. There's something so nice about having a query optimiser on your side (how nice would a perl optimiser be ?!)

I suggest reading through SQL for web nerds by Philip Greenspun. It uses Oracle for it's examples, but the ideas are what you want. All the Oracle stuff directly transaltes to Postgres anyway (except for the tree queries). Don't let the fact that it was written years ago bother you - RDBMS's and SQL have not changed in any way that would make the ideas presented irrelevant.

It's worth learning this stuff well - I am constantly working on projects hampered by poor database design that is very hard to change down the track. Learn the theory, and databases will be your friends...