in reply to Re: mysql's join too slow; using Perl to compare two tables
in thread mysql's join too slow; using Perl to compare two tables
Postgres, on the other hand, seems to take the same time to do inner, outer, or whatever style joins with no performance penalty.
... Unless you don't have the necessary columns indexed, in which case performance can appear to suck mightily, particularly once you've left a small, tidy test environment and start dealing with huge piles of customer data.