Draft: (DO NOT MERGE) Draft: Keeps for desired sharding key backfills
What does this MR do and why?
Not for merging. Similar to !139747, these are single-use keeps.
Status of Keeps
Small tables
Reference issue: #429173 (closed)
Steps:
- Add column, index and FK, start backfill
- Keep: BackfillDesiredShardingKeySmallTable
- Status: Ready, several MRs merged ✅ 
 
- Keep: 
- Finalize backfill
- Keep: OverdueFinalizeBackgroundMigration(not part of this MR)
- Status: Ready ✅ (runs automatically)
 
- Keep: 
- Add not null constraint
- Keep: BackfillDesiredShardingKeySmallTableStep3
- Status: Ready, not yet run ✅ 
 
- Keep: 
Large tables
Reference issue: #429174 (closed)
Steps:
- Add column and async index, start backfill
- Keep: BackfillDesiredShardingKeyLargeTable
- Status: Ready, not yet run ✅ 
 
- Keep: 
- Finalize backfill
- Keep: OverdueFinalizeBackgroundMigration(not part of this MR)
- Status: Ready ✅ (runs automatically)
 
- Keep: 
- Finalize aynsc index, add invalid FK and not null constraint, schedule async validation of FK and not null constraint
- Keep: BackfillDesiredShardingKeyLargeTableStep3
- Status: Ready, not yet run ✅ 
 
- Keep: 
- Finalize async FK and not null constraints
- Keep: BackfillDesiredShardingKeyLargeTableStep4
- Status: Ready, not yet run ✅ 
 
- Keep: 
Edited  by Tiger Watson