I don't know if every country has a 'summer time' period like there is in the UK so i will explain it.
Basically we put the clocks forward for an hour in April then put them back for an hour in October. On day in April the clocks are put forward an hour at 2am. The time goes from 2:00:00am GMT to then being 3:00:01AM (least i think it does, i'm asleep). One day in October the clocks are put back an hour at 2:00 BST to 1:00GMT. So In October the time will be 1:00:00am BST then 1:30:00am BST then when it reaches 2:00:00 BST the time is put back an hour to 1:00:00am GMT.
I have data written to my database every minute and i need to be able to order it by date/time and i don't know how to do it for the 2 hours in the night in October when the clocks are put back. For those 2 hours i will have data that looks a bit like like this
Please can you advise how I might sort this data?