Re: [PERFORM] Performance of a nested loop, whose inner loop uses an index scan.

Hi Matheus: Thanks for your prompt answer. It's for a web application. This part of the application allows to export the answers to a CSV file. So pagination isn't possible here. The user can choose among several filters. The group of the courses is one of them. She

Re: [PERFORM] Performance of a nested loop, whose inner loop uses an index scan.

On Wed, Oct 19, 2016 at 8:54 AM, negora wrote: > Nested Loop (cost=245.92..383723.28 rows=7109606 width=38) (actual > time=1.091..2616.553 rows=8906075 loops=1) > I wonder about the use-case for this query, because it returns more than 8M rows, so 2.6 seconds that sounds that much for so ma

[PERFORM] Performance of a nested loop, whose inner loop uses an index scan.

Hello: I've a question about the performance of a query plan that uses a nested loop, and whose inner loop uses an index scan. Would you be so kind to help me, please? I'm using PostgreSQL 9.5.4 on Ubuntu 14.04 64-bit (kernel 4.8.2). I've 3 tables, which are "answers", "test_completions" and "cou