Daylight savings time can cause problems in a distributed database system if data is synchronized during the hour that the time changes. In fact, you can lose data. This is only an issue in the autumn when the time goes back and there is a one-hour period that can be ambiguous.
To deal with daylight savings time, you have four possible solutions:
Ensure that the consolidated database server is using UTC time.
Turn off daylight savings time on the consolidated database server.
Shut down for an hour when the time changes.
Use UTC timestamps in your download TIMESTAMP columns and use either a generate_next_last_download_timestamp or modify_next_last_download_timestamp script to provide a UTC timestamp for the next last download timestamp.
Discuss this page in DocCommentXchange.
|Copyright © 2012, iAnywhere Solutions, Inc. - SQL Anywhere 12.0.1|