På onsdag 16. mars 2016 kl. 14:53:04, skrev Andreas Joseph Krogh < andr...@visena.com <mailto:andr...@visena.com>>: På onsdag 16. mars 2016 kl. 14:37:27, skrev Tom Lane <t...@sss.pgh.pa.us <mailto:t...@sss.pgh.pa.us>>: Andreas Joseph Krogh <andr...@visena.com> writes: > 1. Why isnt' folder_id part of the index-cond?
Because a GIN index is useless for sorting. > 2. Is there a way to make it use the (same) index to sort by > received_timestamp? No. > 3. Using a GIN-index, is there a way to use the index at all for sorting? No. > 4. It doesn't seem like ts_rank uses the index for sorting either. Same reason. regards, tom lane So it's basically impossible to use FTS/GIN with sorting on large datasets? Are there any plans to improve this situation? Thanks. This paper talks about ORDER BY optimizations for FTS (starting at slide 6 and 7): http://www.sai.msu.su/~megera/postgres/talks/Next%20generation%20of%20GIN.pdf This indicates some work is being done in this area. Oleg, if you're listening, do you guys have any exiting news regarding this? -- Andreas Joseph Krogh CTO / Partner - Visena AS Mobile: +47 909 56 963 andr...@visena.com <mailto:andr...@visena.com> www.visena.com <https://www.visena.com> <https://www.visena.com>
