What would be the best approach to handle the following case with Django?
Django needs access to a database (in MariaDB) in which datetime values are stored in UTC timezone, except for one table that has all values for all of its datetime columns stored in local timezone (obviously different that UTC). This particular table is being populated by a different system, not Django, and for some reasons we cannot have the option to convert the timestamps in that table to UTC or change that system to start storing the values in UTC. The queries involving that table are read-only, but may join data from other tables. The table itself does not have a foreign key but there are other tables with a foreign key to that table. The table is very big (millions of rows) and one of its datetime columns is part of more than one indexes that help for making optimized queries.
I am asking your opinion for an approach to the above case that would be as seamless as it can be, preferably without doing conversions here and there in various parts of the codebase while accessing and filtering on the datetime fields of this "problematic" table / model. I think an approach at the model layer, which will let Django ORM work as if the values for that table were stored in UTC timezone, would be preferable. Perhaps a solution based on a custom model field that does the conversions from and back to the database "transparently". Am I thinking right? Or perhaps there is a better approach?