Re: Proposed patch: make SQL interval-literal syntax work per spec

Ron Mayer <rm_pg@cheapcomplexdevices.com> writes:
> Trying to do the SQL-standard output now, and have a question
> of what to do in the SQL-standard mode when trying to output
> an interval that as both a YEAR and a DAY component.

> AFAICT the SQL standard doesn't let you have both, so the
> "SQL-standard" output actually won't be.

The reason it's not SQL-standard is the data value isn't.
So not a problem.  Someone conforming to the spec limits on
what he puts in will see spec-compliant output.  I think all
you need is 'yyy-mm dd hh:mm:ss' where you omit yyy-mm if
zeroes, omit dd if zero, omit hh:mm:ss if zeroes (but maybe
only if dd is also 0?  otherwise your output is just dd which
is uncomfortably ambiguous).
        regards, tom lane