[tz] Rules for TZ+ database

[Guy Harris]

On Sep 5, 2013, at 11:58 AM, Lester Caine <lester at lsces.co.uk> wrote:

> If we were just typing in raw information, then there would not be a problem, but having gathered growing volumes of data which includes a lot of accurate time material then normalizing the data to UTC is the next stage to ensure events are correct chronologically across time zones. If the calendar of events is correct in 1970 it should also be connect in 1969 and any year before. My first experience of this was with RECENT calendars where meetings were getting scheduled wrong 6 months later because one application was not bothering with daylight saving and another was ... even though both were storing as UTC. Some of my customers are looking to load archive data beyond the 20 years history we already have and that will go back past 1970, so how do I ensure that normalization of 1970 data will match 1969 stuff?

By either

	1) using your own un-winnowed version of the tzdb

or

	2) only using systems where the vendor guarantees that they're offering an un-winnowed version of the tzdb, if there are any such systems.