environment variables

I've noticed postgres uses some environment variables such as $PGDATA. Is
there a standard postgres environment variable for the current database?

I'd like something where we can have aliases and such access the db without
the user having to know what the name is

alias sql='psql -d $PGDATABASE'

type thing.

Thanks,


        Jed S. Walker
        Senior Database Administrator
        Comcast Media Centers
        Phone:    303.267.6759
        Email:     jed_walker@cable.comcast.com

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