Обсуждение: Re: [BUGS] BUG #7722: extract(epoch from age(...)) appears to be broken
I have developed the attached doc patch to address your very clear illustration that our documentation is lacking in this area. --------------------------------------------------------------------------- On Tue, Dec 4, 2012 at 08:18:31PM +0100, Francisco Olarte (M) wrote: > > Wow, that is a weird case. In the first test, we count the number of > > days because it is less than a full month. In the second case, we call > > it a full month, but then forget how long it is. Not sure how we could > > improve this. > > I do not think this needs to be improved, the problem is given two > dates you can substract them in three different ways, > > 1.- (year months)+(days)+(hours minutes seconds), which is what age > does and is documented as such. > > folarte=# select age('2013-11-24 16:41:31','2012-10-23 15:56:10'); > age > ----------------------------- > 1 year 1 mon 1 day 00:45:21 > (1 row) > > Which is apropiate for things like 'I'm xxx old' > > 2.- (days)+(hours-minutes-seconds), which is what substractint dates > do ( or seems to do for me, as I've done: > > select timestamp '2013-11-23 16:41:31' - '2012-10-23 15:56:10'; > ?column? > ------------------- > 396 days 00:45:21 > > Which I can not find a use for, but there sure are and I'm doomed to > find one soon. > > 3.- Exact duration ( I do this a lot at work as I need to calculate > call durations ): > > folarte=# select extract(epoch from timestamp '2013-11-23 16:41:31') - > extract(epoch from timestamp '2012-10-23 15:56:10'); > ?column? > ---------- > 34217121 > (1 row) > > folarte=# select (extract(epoch from timestamp '2013-11-23 16:41:31') > - extract(epoch from timestamp '2012-10-23 15:56:10')) * interval '1 > second'; > ?column? > ------------ > 9504:45:21 > (1 row) > > The problem I see is intervals are really complicated and difficult to > undestand, so it is at most a documentation problem ( people usually > understimate the difficulty of working with them, I see this a lot at > work ). > > Francisco Olarte. -- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.com + It's impossible for everything to be true. +
Вложения
On Fri, Aug 23, 2013 at 09:36:58PM -0400, Bruce Momjian wrote: > > I have developed the attached doc patch to address your very clear > illustration that our documentation is lacking in this area. Patch applied. It will appear in PG 9.4. -- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.com + It's impossible for everything to be true. +
Re: Re: [BUGS] BUG #7722: extract(epoch from age(...)) appears to be broken
От
Peter Eisentraut
Дата:
On 9/3/13 1:25 PM, Bruce Momjian wrote: > On Fri, Aug 23, 2013 at 09:36:58PM -0400, Bruce Momjian wrote: >> >> I have developed the attached doc patch to address your very clear >> illustration that our documentation is lacking in this area. > > Patch applied. It will appear in PG 9.4. This broke the documentation build: openjade:func.sgml:6434:37:E: character data is not allowed here
On Tue, Sep 3, 2013 at 03:59:57PM -0400, Peter Eisentraut wrote: > On 9/3/13 1:25 PM, Bruce Momjian wrote: > > On Fri, Aug 23, 2013 at 09:36:58PM -0400, Bruce Momjian wrote: > >> > >> I have developed the attached doc patch to address your very clear > >> illustration that our documentation is lacking in this area. > > > > Patch applied. It will appear in PG 9.4. > > This broke the documentation build: > > openjade:func.sgml:6434:37:E: character data is not allowed here Oops, sorry. Fixed. My apologies. -- Bruce Momjian <bruce@momjian.us> http://momjian.us EnterpriseDB http://enterprisedb.com + It's impossible for everything to be true. +