David Rysdam <drysdam@ll.mit.edu> writes:
> According to what I've been able to find:
> A = predicted time to first returned row in milliseconds
^^^^^^^^^^^^ arbitrary units
> B = total cost in arbitrary units
> C = actual time to first returned row in milliseconds
> D = actual total time in milliseconds
> 2) Does EXPLAIN ANALYZE add a lot of overhead that is being measured here?
Yes, its per-row overhead can be significant. Depends on what the query
plan actually is, and how many rows go through, which you didn't say...
regards, tom lane