Re: Postgres 11: Table Partitioning and Primary Keys
On Tue, Jul 09, 2019 at 06:59:59PM -0400, Tom Lane wrote: > Alvaro Herrera writes: >> >> >>Unique constraints on partitioned tables (as well as primary keys) >>must constrain all the partition key columns. This limitation exists >>because PostgreSQL can only enforce >>uniqueness in each partition individually. >> >> > >> I'm not really sure about the "must constrain" verbiage. Is that really >> comprehensible? > > I think "must include" might be better. +1. >> which may not be the pinnacle of clarity, but took some time to craft >> and I think is correct. Also it doesn't mention primary keys >> explicitly; maybe we should patch it by adding "(as well as a primary >> key)" right after "a unique constraint". Thoughts? > > I'd leave that alone. I don't think the parenthetical comment about > primary keys in your new text is adding much either. Agreed with not bothering about this block and not adding the parenthetical comment. -- Michael signature.asc Description: PGP signature
Re: Ambiguous language in Table 8.13. Special Date/Time Inputs [EXT]
> I actually agree with your opinion that "midnight" is fine. > That text has been that way for over fifteen years[1], and > nobody's complained before that it was ambiguous. Conversely, how many users over the past fifteen years have read that table, and then felt compelled (as I did) to run a query such as select 'today'::timestamp,'yesterday'::timestamp,'tomorrow'::timestamp; on their PostgreSQL cluster to clear the ambiguity for themselves? Best regards David Harper Wellcome Sanger Institute, Cambridge, England -- The Wellcome Sanger Institute is operated by Genome Research Limited, a charity registered in England with number 1021457 and a company registered in England with number 2742969, whose registered office is 215 Euston Road, London, NW1 2BE.
Re: Ambiguous language in Table 8.13. Special Date/Time Inputs [EXT]
On 7/10/19 6:13 AM, David Harper wrote: >> I actually agree with your opinion that "midnight" is fine. >> That text has been that way for over fifteen years[1], and >> nobody's complained before that it was ambiguous. > > Conversely, how many users over the past fifteen years have read that table, > and then felt compelled (as I did) to run a query such as > > select 'today'::timestamp,'yesterday'::timestamp,'tomorrow'::timestamp; > > on their PostgreSQL cluster to clear the ambiguity for themselves? I've heard of one, but only just recently :) If we were to s/midnight/00:00:00/ we'd probably want to do it everywhere midnight appears. This occurs in a few places in the docs: https://www.postgresql.org/docs/current/functions-formatting.html () https://www.postgresql.org/docs/current/protocol-replication.html (XlogData section) and there are some various code comments as well. Count me as a +0 vote, as I've always interpreted it the way Bruce & Tom said upthread, but if we want to change it I can write a patch. Jonathan signature.asc Description: OpenPGP digital signature
Re: Ambiguous language in Table 8.13. Special Date/Time Inputs [EXT]
On Wed, Jul 10, 2019 at 01:32:31PM -0400, Jonathan Katz wrote: > On 7/10/19 6:13 AM, David Harper wrote: > >> I actually agree with your opinion that "midnight" is fine. > >> That text has been that way for over fifteen years[1], and > >> nobody's complained before that it was ambiguous. > > > > Conversely, how many users over the past fifteen years have read that > > table, and then felt compelled (as I did) to run a query such as > > > > select 'today'::timestamp,'yesterday'::timestamp,'tomorrow'::timestamp; > > > > on their PostgreSQL cluster to clear the ambiguity for themselves? > > I've heard of one, but only just recently :) > > If we were to s/midnight/00:00:00/ we'd probably want to do it > everywhere midnight appears. This occurs in a few places in the docs: > > https://www.postgresql.org/docs/current/functions-formatting.html () > https://www.postgresql.org/docs/current/protocol-replication.html > (XlogData section) > > and there are some various code comments as well. > > Count me as a +0 vote, as I've always interpreted it the way Bruce & Tom > said upthread, but if we want to change it I can write a patch. The thing I don't like about 00:00:00 is that it is a lot of information to say "the start of the day", while I assumed midnight was clear on that. If we can find a way to say "start of the day (midnight)", that would work. -- Bruce Momjian http://momjian.us EnterpriseDB http://enterprisedb.com + As you are, so once was I. As I am, so you will be. + + Ancient Roman grave inscription +
Re: Ambiguous language in Table 8.13. Special Date/Time Inputs [EXT]
Bruce Momjian writes: > The thing I don't like about 00:00:00 is that it is a lot of information > to say "the start of the day", while I assumed midnight was clear on > that. If we can find a way to say "start of the day (midnight)", that > would work. One really simple way to make it shorter is to say "00:00", leaving out the seconds. regards, tom lane
