The other thing I would try is writing a new Dash app with some dummy data and dummy callbacks that matches the shape & architecture of your existing app and see if you can reproduce the error from scratch. This is a great way to debug and get to “root cause” of issues as, as ...
We don't create a new metadata table (in SQL) for each of the tframes, so when we try to write the metadata, we get this sqlite3.IntegrityError: UNIQUE constraint failed: equities.sid or even `sqlite3.IntegrityError: UNIQUE constraint failed: exchanges.exchange. In SQL a UNIQUE integrity ...