Tom Lane wrote:
The idea I just had was: why do we need EXPLAIN ANALYZE to run to
completion? In severe cases like this thread, we might be able to
discover the root cause by a *partial* execution of the plan, as long as
it was properly instrumented. That way, the OP might have been able to
discover the root cause himself...
I don't think that helps, as it just replaces one uncertainty by
another: how far did the EXPLAIN really get towards completion of the
plan? You still don't have any hard data.
But at least you have some data, which is better than no data. Even knowing that the plan got stuck on a particular node of the query plan could be vital information. For a query that never finishes, you can't even find out where it's getting stuck.
That's why Simon's proposal might help in some particularly difficult situations.
Regards,
Craig
