Re: Bug with timestamp !!!

On Sun, May 13, 2001 at 11:27:45AM -0400, Tom Lane wrote:
> "Eric G. Miller" <egm2@jps.net> writes:
> > While I don't see such dramatic results with this bad input data, I did
> > run across something a little peculiar:
>
> With what PG version?  On what platform?

# select version();
                            version
---------------------------------------------------------------
 PostgreSQL 7.1.1 on i686-pc-linux-gnu, compiled by GCC 2.95.4

Debian GNU/Linux, "unstable"

GNU libc6 2.2.3-1

> Comparing 7.1.1 against 7.0.*, I note that the resolution of "illegal"
> times during a DST jump has changed, at least on my platform (HPUX 10.20).
> 7.0.* resolves the time backwards whereas current sources resolve
> forwards: "select timestamp('2001-04-01 02:02:02')" yields
>     2001-04-01 01:02:02-05    in 7.0.2
>     2001-04-01 03:02:02-04  in current
> Since this is dependent on how the local mktime() library routine
> reacts to "illegal" times, some platform-to-platform variation is to be
> expected.  Your example looks like mktime() must actually have some
> internal state on your machine, causing its result to depend on what
> it was asked previously :-(

Yes, I think the timezone environment variable is being carried. I wrote
a small test program, and the same weirdness happens.  So, it's not
specifically a PostgreSQL issue.

--
Eric G. Miller <egm2@jps.net>