Chamber 71 · Pattern Vault
Mirror Weave
CTE + LEFT JOIN
Clear the previous chamber to unlock this one. You can still preview the briefing.
Briefing
Every weaver must appear in the mirror — even those with no threads. COALESCE fills blank spools with zero.
Objective
Return weaver name and max_tension from WITH loom AS (weavers) LEFT JOIN threads, COALESCE(MAX(tension), 0), grouped by name.
Hint
WITH loom AS (SELECT id, name FROM weavers), LEFT JOIN threads, MAX + COALESCE, GROUP BY name.
Chamber schema
weavers2 colsAll vault weavers
threads3 colsOptional thread assignments
Results appear here after you run a query. Correct rows alone are not enough — the Warden must seal your loot.
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