DateTime Math?

OK, yes, I missed that part where the next start date is taken from the mod date of the last modified record. Very good.

Good point. I’ve got some checks built in and Iog any errors so I would imagine that if a user has a record locked and I try to update it I’ll get an error. No? This is so low traffic that I could probably get by with doing the sync off hours for starters.

If your application is just remembering the time of the last update and you are then creating a new start and end time (with some overlaps) to retrieve the next n minutes worth then you can remember the last date & time in seconds or as a string and just add the interval. I think daylight savings would be more of an issue if the server is using a time zone with daylight savings because the update time will jump twice during the year. If that is the case then you will need to adjust your date & time in sync with the server time zone.

It is sensible for database server systems to use UTC (almost the same as GMT) if the users are crossing time zones although you can use any if the time zone is stored with the time or if the time zone is fixed. If your application uses UTC and the server uses UTC then there should be no time jumps. Your application may then need to convert UTC to the TZ of the user for display purposes allowing for DST when required.