i've been working on a new weblog-preference for specifying the timezone of a weblog. now it basically works, there's just one question i'd like to discuss: should we store timestamps in antville's database in GMT or keep it like it is (= local time)?

first options means that not only are timestamps in the database stored in GMT but also the appserver (just Helma, not the server) itself must run in GMT (specified in server.properties, specifying the timezone in apps.properties has no effect) - which means that every other app using the same Helma-installation is forced to adjust time according to a specified timezone itself.

second option means that antville will have to do a bit more of time-calculating (calc local time from DB back to GMT and then use the offset according to the specified timezone).

i tend to store timestamps in database in GMT, although this means that antville would get another default-property (the timezone of an antville-installation). and all existing timestamps in database must be converted to GMT. what ya think?

but to give at least some feedback i would consider the second option as my favourite one.

You are quite right to spend some time thinking about how this should be handled. And, having dealt with the problem for many years at TVGuide---where we had to worry about timezones a lot---I am confident that there is no `right' answer. But there are some wrong ones.

For example, I think it is wrong in the current Antville to not show `zone'. I guessed that the time was probably UTC but I think for clarity it should always be shown.

My personal preference is to show the time in the timezone of the Writer, if you are able to determine that. I say this because the one useful inference I make from `time' is, for example, that messages written at 0300 may have a different tenor than those written at 1200 or 1800. If you can't show timezone of the writer then either UTC or the timezone of the reader is ok. From a storage standpoint, I guess I'd store in UTC and keep the TZ of the writer as an offset.

[I couldn't figure out how to attach this to the `reply' immediately above, so I added it as a new comment.]

I understand that it might be difficult to know the time zone of the writer, but most conventional EMail seems to do it pretty well (most EMail that I get shows up with Date/Time followed by something like -0500 to indicate Eastern Standard Time) so I'd have naively guessed that you could get your hands on local time' when someone was making an entry. But I don't know enough to know' that for sure.

I don't quite understand the `switch the whole Weblog' problem though. I'd be interested if you could explain it a bit more...