On Fri, Apr 02, 2021 at 10:21:26PM -0400, Bruce Momjian wrote: > I wish I could figure out how to improve it any futher. What is odd is > that I have never seen this reported as a problem before. I plan to > apply this early next week for PG 14.
On Fri, Apr 02, 2021 at 01:05:42PM -0700, Bryn Llewellyn wrote: > br...@momjian.us wrote: > > Yes, looking at the code, it seems we only spill down to one unit, not > > more. I think we need to have a discussion if we want to change that. If this is a bug, then there's no deadline - and if you're proposing a behavior change, then I don't think it's a good time to begin the discussion. > https://www.postgresql.org/docs/current/datatype-datetime.html#DATATYPE-INTERVAL-INPUT > « …field values can have fractional parts; for example '1.5 week' or > '01:02:03.45'. Such input is converted to the appropriate number of months, > days, and seconds for storage. When this would result in a fractional number > of months or days, the fraction is added to the lower-order fields using the > conversion factors 1 month = 30 days and 1 day = 24 hours. For example, '1.5 > month' becomes 1 month and 15 days. Only seconds will ever be shown as > fractional on output. » Your patch changes what seems to be the intended behavior, with the test case added by: |commit 57bfb27e60055c10e42b87e68a894720c2f78e70 |Author: Tom Lane <t...@sss.pgh.pa.us> |Date: Mon Sep 4 01:26:28 2006 +0000 | | Fix interval input parser so that fractional weeks and months are | cascaded first to days and only what is leftover into seconds. This And documented by: |commit dbf57d31f8d7bf5c058a9fab2a1ccb4a336864ce |Author: Tom Lane <t...@sss.pgh.pa.us> |Date: Sun Nov 9 17:09:48 2008 +0000 | | Add some documentation about handling of fractions in interval input. | (It's always worked like this, but we never documented it before.) If you were to change the behavior, I think you'd have to update the documentation, too - but I think that's not a desirable change. I *am* curious why the YEAR, DECADE, CENTURY, AND MILLENIUM cases only handle fractional intervals down to the next smaller unit, and not down to seconds/milliseconds. I wrote a patch to handle that by adding AdjustFractMons(), if we agree that it's desirable to change. -- Justin
