I would *not* use the default version of Postgres shipped with any particular distribution. Use 7.3.3 because that is the latest released version. Or, as Shridhar mentioned in his post, the are a number of pretty significant performance improvements in 7.4 (which is in feature freeze and scheduled to go into beta on 21 July). If you are in an exploratory/test phase rather than production right now, I'd say use the 7.4 beta for your comparisons.
Well, I could start by testing 7.4, however I'd have to go back to the stable version once we're ready to use it a production environment. So, I might as well stick with eveluating the production version.
How soon do you think you'll be in production? PostgreSQL beta testing usually seems to run about 2 months or so -- if you won't be in production before October, it is a good bet that Postgres 7.4 will be out or at least in release candidate by then.
But it really depends on your specific application. If you use lots of "WHERE foo IN (SELECT ...)" type queries, you'll need to rewrite them in 7.3.3 or earlier, but in 7.4 they will probably work fine. Also, if you do much in the way of aggregate queries for reporting, 7.4 will likely give you a significant performance boost.
If money is truly not a problem, but time is, my advice is to hire a consultant. There are probably several people on this list that can fill that role for you. Otherwise read the archives and ask lots of specific questions.
Once we're ready to go with postgresql in a production environment we may indeed need to hire a consultant. Any suggestions whom I should contact? (We're in the San Diego area)
Um, actually, I live in the San Diego area ;-)
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