## Summary
- Drop all 8 foreign key constraints on TaskRun. The run listing path is
now fully ClickHouse-backed so we no longer need Postgres to enforce
referential integrity on this table. The FK constraints add write
overhead on every insert/update with no remaining benefit. Prisma
queries are unaffected.
- Remove PostgresRunsRepository and its associated feature flag
(runsListRepository), which was the last remaining code path querying
TaskRun directly for list/count operations.
- Drop three indexes that were only useful for the Postgres run list
path and have no remaining query consumers:
- TaskRun_runtimeEnvironmentId_id_idx — was the cursor pagination index
for PostgresRunsRepository; superseded by the (runtimeEnvironmentId,
createdAt DESC) composite index
- TaskRun_scheduleId_idx — redundant with the (scheduleId, createdAt
DESC) composite index; no direct Postgres queries filter by scheduleId
alone
- TaskRun_rootTaskRunId_idx — no queries filter TaskRun by rootTaskRunId
as a WHERE clause anywhere in the codebase
All index drops use CONCURRENTLY IF EXISTS to avoid table locks in
production.
## Test plan
- pnpm run db:migrate:deploy applies all migrations cleanly
- pnpm run typecheck --filter webapp passes
- Run list pages load correctly in the dashboard (ClickHouse path)
- Scheduled task runs still trigger and appear correctly
Matt Aitken
0e14b6d750