Expected CASE facts are assertions only.
Honest by construction
Expected CASE facts are assertions only.
compiler is source of truth \text{compiler is source of truth} compiler is source of truth
Render checked rows
The guarded CASE expression renders 4 output rows after recomputation.
checked rows = 4 \text{checked rows}=4 checked rows = 4
CASE-expression examples are tiny finite row transforms with SQL-style TRUE/FALSE/UNKNOWN logic; SQL dialect completeness, type coercion, optimizer behavior, indexing, and product claims are out of scope.
Honest by construction: base rows Honest by construction: base rows name score status Ada 90 active Bea 40 active Cal NULL active Dee 70 paused CASE branch evaluation CASE branch evaluation source values evaluations result resultSource 0 [Ada, 90, active] [{branch:0, truth:TRUE, chosen:yes}, {branch:1, truth:TRUE, chosen:no}] high branch 0 1 [Bea, 40, active] [{branch:0, truth:FALSE, chosen:no}, {branch:1, truth:FALSE, chosen:no}] low ELSE 2 [Cal, NULL, active] [{branch:0, truth:UNKNOWN, chosen:no}, {branch:1, truth:UNKNOWN, chosen:no}] low ELSE 3 [Dee, 70, paused] [{branch:0, truth:FALSE, chosen:no}, {branch:1, truth:TRUE, chosen:yes}] mid branch 1 CASE output rows CASE output rows name score status bucket Ada 90 active high Bea 40 active low Cal NULL active low Dee 70 paused mid CASE facts CASE facts fact value inputRowCount 4 branchCount 2 outputRowCount 4 firstTrueRows 2 elseRows 2 nullElseRows 0 unknownSkipped 2 rowOrder source_order
Try to tamper
Wrong expected facts, derived sidecars, duplicate aliases, missing columns, bools, floats, and invalid comparisons fail closed.
tamper rejected \text{tamper rejected} tamper rejected
Summary
The book shows exact finite CASE behavior only; product SQL behavior is outside the model.
scoped CASE model \text{scoped CASE model} scoped CASE model