Guy, You are right. As we understand it, countries may make an announcement that they will be observing DST this year on such and such a date. What we need is to keep track of these pronouncements as they relate to our flight schedules. We will have to map countries & cities to the locations. I will check out the resources you site here. This list has been very helpful! Bonnie K. O'Neil CBIP, CDMP Enterprise Data Architect Travelport Global Technology Solutions Office: 303-397-5239 Mobile: 303-725-1737 -----Original Message----- From: Guy Harris [mailto:guy@alum.mit.edu] Sent: Friday, February 04, 2011 4:12 PM To: tz@lecserver.nci.nih.gov Subject: Re: Date Countries Switch to/from DST On Feb 4, 2011, at 9:15 AM, O'Neil, Bonnie wrote:
I need to get a dump of the tz database for all countries in the world, which timezone they are in, and what date they switch on/off DST.
Note that "the tz database", in the sense of the database available for FTP from elsie.nci.nih.gov (which is where the tz-link.htm page points), and which this list discusses, doesn't directly have "countries"; the name of a "time zone" in the database corresponds to a "location" - to quote the tz-link.htm page: Each location in the database represents a national region where all clocks keeping local time have agreed since 1970. Locations are identified by continent or ocean and then by the name of the location, which is typically the largest city within the region. For example, America/New_York represents most of the US eastern time zone; America/Phoenix represents most of Arizona, which uses mountain time without daylight saving time (DST); America/Detroit represents most of Michigan, which uses eastern time but with different DST rules in 1975; and other entries represent smaller regions like Starke County, Indiana, which switched from central to eastern time in 1991 and switched back in 2006. I infer from your company's name and Web site that one thing you probably need is a way to map a geographical location to a tz database location (for example, "what timezone is Paris in and when do they switch on/off DST?"). The tz database doesn't itself provide that, but at http://efele.net/maps/tz/world/ you can get a file that shows the boundaries of tz database locations; at http://www.manifold.net/info/freestuff.shtml are a bunch of data sets, include a map of "World Time Zones", although they don't say whether that's a map of tz database locations or not. If you are not the intended recipient of this e-mail message, please notify the sender and delete all copies immediately. The sender believes this message and any attachments were sent free of any virus, worm, Trojan horse, and other forms of malicious code. This message and its attachments could have been infected during transmission. The recipient opens any attachments at the recipient's own risk, and in so doing, the recipient accepts full responsibility for such actions and agrees to take protective and remedial action relating to any malicious code. Travelport is not liable for any loss or damage arising from this message or its attachments.