Re: 30-70 seconds query...

I said:
> PG 7.4 will be better prepared to handle this sort of query, but I don't
> think it will realize that the T1/T2 left join could be reduced to a
> plain join given these conditions

I take that back --- actually, the algorithm used in CVS tip *does*
deduce that all these left joins can be plain joins.

Don't suppose you'd like to experiment with a current snapshot to see
how well it does for you?

            regards, tom lane