"Sabin Coanda" wrote:
> How do you explain the cost is about ten times lower in the 2nd
> query than the first ?
To elaborate on Pierre's answer:
In the first query, you scan the entire table and execute the "f1"
function on each row. In the second query you pass the entire table
just count
How do you explain the cost is about ten times lower in the 2nd query
than the first ?
Function call cost ?
Can you EXPLAIN ANALYZE ?
--
Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-
Hi there,
I have a simple aggregate query: SELECT count("PK_ID") AS "b1" FROM "tbA"
WHERE "PK_ID" > "f1"( 'c1' ), which has the following execution plan:
"Aggregate (cost=2156915.42..2156915.43 rows=1 width=4)"
" -> Seq Scan on "tbA" (cost=0.00..2137634.36 rows=7712423 width=4)"
"Filt
