Kai,
> It would be much nicer to have to write something like: SELECT xyz, abc
> FROM active(tablex); where the function 'active(x)' returns a virtual
> table with all entries from table x where status is > -1. But sadly I
> have no idea how write such a function. Good old O'reilly can't help (or
> i'm to dumb *g*).
http://techdocs.postgresql.org/guides/SetReturningFunctions
Beware, though, that query plan estimation for SRFs is less accurate than for
regular subqueries, so you could end up with unnecessarily slow query
execution. Test!
--
Josh Berkus
Aglio Database Solutions
San Francisco