Re: timestamp with timezone and time zone name

Shridhar Daithankar <ghodechhap@ghodechhap.net> writes:
> I am wondering, why following two values result in a shift by 3.5 hours. I
> would expect them to be identical.

> I understand that canonical time zone names could be ambiguous at times but I
> think IST is not one of them.

I don't know why you'd think that ...

src/timezone/tznames/Asia.txt:IST     19800    # Indian Standard Time
src/timezone/tznames/Asia.txt:IST      7200    # Israel Standard Time

... and there's some references to "Irish Summer Time" in the Olson
database, as well.  IIRC, IST was one of the primary problems that
forced us to invent the "timezone_abbreviations" configuration
mechanism.  Try setting that to "India" if you want the 05:30 meaning.

            regards, tom lane