- ALTERs to run: https://gerrit.wikimedia.org/r/c/mediawiki/core/+/642685/1/maintenance/archives/patch-watchlist-wl_notificationtimestamp.sql
- Where to run those changes: all.dblist
- When to run those changes: At any time
- If the schema change is backwards compatible: Yes
- If the schema change has been tested already on some of the test/beta wikis: Tested in beta cluster.
- if the data should be made available on the labs replicas and/or dumps: Yes, data in this table is public
The field is all NULL in enwiki.