Tom, I am afraid that I don't understand. My first example:
wow=# explain analyze select max(click.accesses) from click; QUERY
PLAN
-----------------------------------------------------------------------------------------------------------------
Aggregate (cost=1103.70..1103.70 rows=1 width=8) (actual
time=289.391..289.393 rows=1 loops=1) -> Seq Scan on click (cost=0.00..971.36 rows=52936 width=8) (actual
time=0.013..133.943 rows=52936 loops=1) Total runtime: 289.498 ms
(3 rows)
Time: 290,695 ms
select max() returns only one row... If you mean rows in Seq Scan than
gettimeofday was called (52936+1)*2. Huge value :(
Tom Lane wrote:
> Teodor Sigaev <teodor@sigaev.ru> writes:
>
>>How many times is gettimeofday called?
>
>
> Twice per plan node visit, if you are doing EXPLAIN ANALYZE. (The
> number of "visits" is one more than the number of rows returned.)
>
> regards, tom lane
>
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--
Teodor Sigaev E-mail: teodor@sigaev.ru
