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A keyed upsert looks up its old row by new key instead of identity · case 04

A keyed upsert looks up its old row by new key instead of identity.

Member previewVariant 4 · 3 implementations · 7 checks per implementation

Case contract

Maintain an identity-indexed keyed table while applying [id,newkey,newvalue] upserts. A moved identity retracts its old key/value before adding the new row. Identical upserts emit no change. State and emitted changelog preserve identity distinctions.

Why this case matters

A bounded deterministic data engine model makes representation and changelog faults reproducible.

One recorded failure

Sample boundary fixture

This sample comes from the broken implementation of a controlled reproducer.

Boundary fixture	Actual	Expected	Outcome
move key	`[[[10, 2, 5]], [[10, 2, 5, 1]]]`	`[[[10, 2, 5]], [[10, 1, 4, -1], [10, 2, 5, 1]]]`	Failed

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