| From: | Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> |
|---|---|
| To: | Jeff Janes <jeff(dot)janes(at)gmail(dot)com> |
| Cc: | Amit Kapila <amit(dot)kapila16(at)gmail(dot)com>, Justin Pryzby <pryzby(at)telsasoft(dot)com>, David Steele <david(at)pgmasters(dot)net>, James Coleman <jtc331(at)gmail(dot)com>, Alexey Bashtanov <bashtanov(at)imap(dot)cc>, Emre Hasegeli <emre(at)hasegeli(dot)com>, pgsql-hackers <pgsql-hackers(at)postgresql(dot)org> |
| Subject: | Re: improve transparency of bitmap-only heap scans |
| Date: | 2020-03-24 19:14:30 |
| Message-ID: | 30509.1585077270@sss.pgh.pa.us |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-hackers |
I took a quick look through this patch. While I see nothing to complain
about implementation-wise, I'm a bit befuddled as to why we need this
reporting when there is no comparable data provided for regular index-only
scans. Over there, you just get "Heap Fetches: n", and the existing
counts for bitmap scans seem to cover the same territory.
I agree with the original comment that it's pretty strange that
EXPLAIN doesn't identify an index-only BMS at all; but fixing that
is a different patch.
regards, tom lane
| From | Date | Subject | |
|---|---|---|---|
| Next Message | Andres Freund | 2020-03-24 19:16:51 | Re: Fastpath while arranging the changes in LSN order in logical decoding |
| Previous Message | Andres Freund | 2020-03-24 19:13:46 | Re: Adding a test for speculative insert abort case |