David Link <dlink@xxxxxxxxxxxxx> writes: > The following large EXPLAIN SELECT Statement fails to return, but > continues to take up processing time until it is killed. > [ 52-way join... ] Am I right in guessing that all the sales_xxx tables are the same size and have similar statistics? I think the problem is that the planner is faced with a large set of essentially equivalent plans and isn't pruning the list aggressively enough. That's something we fixed in 8.0. > Postgresql 7.4.8 You really oughta try something newer. On my machine, 7.4.12 plans a 52-way join in about a minute, and 8.0 and 8.1 in under a second. I wonder also if there's not a better way to design the query... maybe a UNION ALL would work better than nested joins. regards, tom lane
