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Lateral correlation treats absent keys as equal keys · case 04

Lateral correlation treats absent keys as equal keys.

Member previewVariant 4 · 3 implementations · 7 checks per implementation

Case contract

For each outer [id,key] row, evaluate matching [key,value] inner rows with a minimum supplied by that outer row. Emit [id,value] in source order, preserving duplicate inner matches. Empty matches emit [id,None] under outer lateral semantics.

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
null key	`[[10, 5]]`	`[[10, null]]`	Failed

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