Timeline for PostgreSQL size of used shared buffer vs actual result size
Current License: CC BY-SA 4.0
12 events
| when toggle format | what | by | license | comment | |
|---|---|---|---|---|---|
| Feb 22 at 10:04 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Oct 21, 2023 at 23:01 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Jun 19, 2023 at 17:07 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Feb 16, 2023 at 4:02 | history | bumped | CommunityBot | This question has answers that may be good or bad; the system has marked it active so that they can be reviewed. | |
| Aug 10, 2022 at 16:08 | answer | added | jjanes | timeline score: 1 | |
| Aug 10, 2022 at 7:06 | comment | added | jdziwbc | @a_horse_with_no_name Thanks! The table was queried right after inserting so it's not been analysed yet => no stats. That's probably why index was used. See db-fiddle: db-fiddle.com/f/9ctDvNSD5zGxB7sxSYDxwS/0 | |
| Aug 10, 2022 at 7:04 | history | edited | jdziwbc | CC BY-SA 4.0 |
added 82 characters in body
|
| Aug 10, 2022 at 5:34 | comment | added | user1822 | Reading a single row through an index lookup requires more I/O operations (=buffer reads) per row than reading a single row through a Seq Scan. I am surprised that Postgres did use an index lookup at all in the second example. | |
| Aug 9, 2022 at 23:00 | comment | added | mustaccio | I don't think you have posted the complete execution plan for the second example, which would give you the answer. There you perform 500 individual index lookups, each fetching one page, plus 500 individual heap fetches. | |
| Aug 9, 2022 at 22:48 | history | edited | jdziwbc | CC BY-SA 4.0 |
edited title
|
| S Aug 9, 2022 at 22:48 | review | First questions | |||
| Aug 9, 2022 at 23:18 | |||||
| S Aug 9, 2022 at 22:48 | history | asked | jdziwbc | CC BY-SA 4.0 |