In this post we’ll look at the behaviour of a SQL Server application that needs to deal with events that are logged over the period of a UK clock change where the clocks change from GMT (Greenwich Mean Time) to BST (British Summer Time).
The data itself is in UTC (which is good), but getting from UTC to the user’s local time can be a major challenge, especially in T-SQL. There are application libraries that make this a lot easier, which is why I recommend bouncing this up to the application layer whenever possible.