perf: add indexes for card relation queries - #566
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Add FK-first indexes for card comments, attachments, checklists, checklist items, and activities to avoid repeated sequential scans in board and card relational queries.
bionicman
marked this pull request as ready for review
August 31, 2026 23:12
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Description
Board and card relation loading repeatedly filters child tables by their foreign key and, for ordered relations, sorts by the relation's ordering column. These tables did not have matching indexes, so PostgreSQL performed repeated sequential scans as the dataset grew.
This adds indexes for:
The schema declarations and generated Drizzle migration are included in the same change.
The issue was reproduced on a real Trello import containing 38 boards and 14,524 cards. The indexed relation tables contained 53,032 comments, 17,384 attachments, 2,221 checklists, 12,613 checklist items, and 67,556 activity rows. The measured board contained 3,236 stored cards across 45 lists; its normal API response included 709 active cards and was approximately 692 KB.
On that dataset, the database portion of the large board query dropped from about 2.9 seconds to 17–29 ms. End-to-end board loading dropped from about 13.1 seconds to 0.35–0.81 seconds. PostgreSQL also selected all five new indexes during normal application traffic after migration.
Type of change
Checklist
Testing
git diff --check upstream/main...HEADpnpm --filter @kan/db typecheckLinked issue
Not applicable: this is a database performance bug fix and does not change product behavior.