fix(drizzle): prevent duplicate latest=true version rows under concurrent/same-second writes#17413
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fix(drizzle): prevent duplicate latest=true version rows under concurrent/same-second writes#17413gonzoblasco wants to merge 2 commits into
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…rent/same-second writes The createVersion function clears prior latest flags with a separate UPDATE guarded by updatedAt < comparison. This guard is too strict: two autosave writes within the same second produce identical updatedAt values, so the < operator skips the earlier row and both keep latest=true. Replace the updatedAt < guard with id < result.id. Version IDs are auto-incremented in SQLite/D1, so any prior version always has a smaller id. This is deterministic and not subject to timestamp collisions. Also adds an assertion to the existing parallel-writes test and a new same-second-writes test that reproduces the exact failure mode from payloadcms#17216. Fixes payloadcms#17216
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Hi, I left an inline comment, please, check it beause it might be useful. Thank you!
…p race The cleanup query used id != result.id, which is vulnerable to an interleaving race: two concurrent writes can insert rows A and B, then B's cleanup runs first (keeps B), then A's cleanup runs second and with != it also clears B — leaving no version with latest=true. Changing to id < result.id ensures each cleanup only touches rows older than its own insert, so a newer concurrent insert is preserved. Also adds a regression test that simulates the exact interleaving pattern described in sviat-barbutsa's review. Refs payloadcms#17413
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The
createVersionfunction in the drizzle adapter clears priorlatestflags with a separate UPDATE guarded byupdatedAt <. This guard is too strict: two autosave writes within the same second produce identicalupdatedAtvalues, so the<operator skips the earlier row and both keeplatest = true. On D1/SQLite this routinely produces duplicate rows under normal autosave editing.The fix: replace
updatedAt <withid < result.id. Version IDs are auto-incremented in SQLite/D1, so any prior version always has a smaller id. This is deterministic and not subject to timestamp collisions.Testing:
expect(docs).toHaveLength(1)to the existing parallel-writes test (was only checkingdocs[0]is defined)updatedAttimestamp and asserts only onelatest = truerowFixes #17216