Aw: Time zone offset in to_char()

> In the above, I worked around the issue using a couple of user-defined functions in PG. That should give a reasonable idea of the desired functionality, but it's not an ideal solution to my problem:
> 1). The first function has as a drawback that it changes the time zone for the entire transaction (not sufficiently isolated to my tastes), while
> 2). The second function has the benefit that it doesn't leak the time zone change, but has as drawback that the time zone is now hardcoded into the function definition, while
> 3). Both functions need to be created in the caching database before we can use them, while we have several environments where they would apply (DEV, pre-PROD, PROD).

Would a function that dispatches its calls to a suitable array of hard-coded functions based on an IN parameter help any ?

Karsten