Re: Mini improvement: statement_cost_limit

Bruce,

> How about a simpler approach that throws an error or warning for
> cartesian products?  That seems fool-proof.

Well, throwing a warning is pretty useless for an unattended application.  

Also, it's perfectly possible to write queries which will never complete 
without a cartesian join.

Basically, *unless* someone has a plan to integrate the greenplum resource 
management stuff sometime soon, I think we should take Hans' idea (pending 
patch quality, of course).  There's an argument to be made that even if we 
took the greenplum resource controller, statement_cost_limit would be much 
simpler and worth having for the small-effort simple-application users.

FYI, the concept behind the Greenplum RM is similar, except that it 
maintains a total "pool" of query costs on a per-role basis.  

-- 
--Josh

Josh Berkus
PostgreSQL
San Francisco