Re: Enable pg_stat_statements extension for limited statements only
Yes, I agree that infrequent statements don't need stats. Actually I was distracted with the use case that I had in mind other than stats, maybe bringing that up will help. If someone's interested how frequent are deletes being run on a particular table, or what was the exact query that ran. Basically keeping track of queries. Although now I'm less convinced if a considerable amount of people will be interested in this, but let me know what you think. On Wed, Nov 30, 2022 at 10:15 AM Tom Lane wrote: > Sayyid Ali Sajjad Rizavi writes: > > Hi, I'd like to propose a change and get advice if I should work on it. > > The extension pg_stat_statements is very helpful, but the downside is > that > > it will take up too much disk space when storing query stats if it's > > enabled for all statements like SELECT, INSERT, UPDATE, DELETE. > > It will only take up a lot of disk space if you let it, by setting > the pg_stat_statements.max parameter too high. > > > For example, deletes do not happen too frequently; so I'd like to be able > > to enable pg_stat_statements only for the DELETE statement, maybe using > > some flags. > > I'm a little skeptical of the value of that. Why would you want stats > only for infrequent statements? > > I'm not denying that there might be usefulness in filtering what > pg_stat_statements will track, but it's not clear to me that > this particular proposal will be useful to many people. > > I wonder whether there would be more use in filters expressed > as regular expressions to match against the statement text. > That would allow, for example, tracking statements that mention > a particular table as well as statements with a particular > head keyword. I could see usefulness in both a positive filter > (must match this to get tracked) and a negative one (must not > match this to get tracked). > > regards, tom lane >
Re: Enable pg_stat_statements extension for limited statements only
Sayyid Ali Sajjad Rizavi writes: > Hi, I'd like to propose a change and get advice if I should work on it. > The extension pg_stat_statements is very helpful, but the downside is that > it will take up too much disk space when storing query stats if it's > enabled for all statements like SELECT, INSERT, UPDATE, DELETE. It will only take up a lot of disk space if you let it, by setting the pg_stat_statements.max parameter too high. > For example, deletes do not happen too frequently; so I'd like to be able > to enable pg_stat_statements only for the DELETE statement, maybe using > some flags. I'm a little skeptical of the value of that. Why would you want stats only for infrequent statements? I'm not denying that there might be usefulness in filtering what pg_stat_statements will track, but it's not clear to me that this particular proposal will be useful to many people. I wonder whether there would be more use in filters expressed as regular expressions to match against the statement text. That would allow, for example, tracking statements that mention a particular table as well as statements with a particular head keyword. I could see usefulness in both a positive filter (must match this to get tracked) and a negative one (must not match this to get tracked). regards, tom lane
Enable pg_stat_statements extension for limited statements only
Hi, I'd like to propose a change and get advice if I should work on it. The extension pg_stat_statements is very helpful, but the downside is that it will take up too much disk space when storing query stats if it's enabled for all statements like SELECT, INSERT, UPDATE, DELETE. For example, deletes do not happen too frequently; so I'd like to be able to enable pg_stat_statements only for the DELETE statement, maybe using some flags. Another possibility is if we can limit the tables to which pg_stat_statements logs results.
