Ron Mayer <rm_pg@cheapcomplexdevices.com> writes:
> Oh. I wasn't proposing 8601-only. Just the one-character
> shorthands like '1Y1M'::interval that postgresql interprets
> as "1 year one minute". No standard specifies anything close
> to that; and any similar standards ask to interpret that M as
> months instead of minutes.
Hmmm. I would say that the problem with that is not that it's
nonstandard but that it's ambiguous. Our documentation about the
interval type says:
interval values can be written with the following syntax:
[@] quantity unit [quantity unit...] [direction]
Where: quantity is a number (possibly signed); unit is microsecond, millisecond, second, minute, hour, day, week,
month,year, decade, century, millennium, or abbreviations or plurals of these units; direction can be ago or empty. The
atsign (@) is optional noise. The amounts of different units are implicitly added up with appropriate sign accounting.
agonegates all the fields.
There isn't anything there that would suggest to a user that 'm' is
well-defined as a unit, much less that it specifically means "minute"
rather than one of the other options. What if we just tweak the code to
reject ambiguous abbreviations?
[ experiments a bit... ] Another interesting point is that "mo",
which is a perfectly unique abbreviation, is rejected. Seems like
the handling of abbreviations in this code could be improved.
regards, tom lane
