Mikhail Rogachev 6522d52016
Feat: Simplify profile showcase preferences (#4854)
* Feat: simplify profile showcase preferences

* Feat: remove old profile showcase preferences on save

* Feat: add getters for showcase entries limits
2024-03-08 17:20:23 +01:00
..
2021-01-08 08:43:16 +01:00

How to write migrations?

We only write up migrations, down migrations are not always possible in sqlite or too complex/too expensive. For example to remove a column you would have to duplicate the table, copy over the data, delete and recreated. This can be very expensive for some tables (user_messages for example), so should not be attempted.

Notes

One issue we faced multiple times is that updates to user_messages can be very expensive, leading to slow upgrade times and interrupted migrations. So avoid writes if not necessary.