[Decision] min/max over a boolean aggregand: pin the cross-driver JSON answer — 0/1 (SQL) vs false/true (both in-memory faces) #11249

Split from #11152 (retriage, 2026-08-23): half (a) — sum/avg boolean conformance cases, settled by #11065's precedent — stays on #11152 and is dispatchable. This card carries half (b), the genuinely unpinned contract question, which is 协议变化类别 ⇒ manual floor.

The question

When an aggregation query takes min or max over a boolean column, what JSON value does the platform contract promise?

• SQLite / the SQL family: MIN(col)/MAX(col) over a boolean answer 0 / 1.
• objectql's in-memory fallback (in-memory-aggregation.ts) and driver-memory both reduce with </> and answer false / true.

Unlike #11065 (driver-memory was the lone outlier; two faces pinned the answer), here the two in-memory faces agree with each other and differ from SQL — precedent does not settle it. Whatever is chosen becomes the expected value in AGGREGATION_ROWS conformance cases and forces the losing side to convert.

[facets-block]

• 实际业务需求:布尔列上的 min/max 在真实分析里语义是「是否存在任一 false / 任一 true」——用户拿到 0/1 或 false/true 都能用,但两驱动答案不同就是同一查询两个结果,由调用方看不见的驱动能力位决定;真实需求是一致,不是哪个字面量。
• 项目长远合理性:平台契约面(REST/JSON)里布尔字段的读值恒为 true/false;聚合结果突然变 0/1 是 SQL 存储表示的泄漏。选 false/true 让契约与字段类型系统自洽;选 0/1 则是让存储实现定义契约。
• 防 AI 写代码犯错:AI 写下游代码时会对布尔字段做 === true 判断——0/1 会静默永假。收敛到 false/true(SQL 侧结果在驱动层归一化)是结构上更难写错的一侧。
• 创业阶段不扩散需求:两选项实现代价接近(都是在少数驱动侧加一层归一化);不存在「先不做」选项——[finding] AGGREGATION_ROWS has no boolean column, so the cross-driver aggregation conformance family cannot see a boolean aggregand on any face #11152 的列一加,期望值必须写死。

推荐 B(false/true,置信度高):四轴同向——契约按字段类型说话,SQL 驱动在聚合读出侧把 0/1 归一化为布尔;与布尔字段普通读取路径的既有归一化同族。本分析看不见什么:driver-sql 各方言布尔存储表示的现状差异(TINYINT/BOOLEAN/INTEGER),归一化实现成本以实测为准;PG 对 avg(boolean) 可能直接报错(#11152 half (a) 的实测项,读数会回贴该卡)。

裁决格式:回「A」(= 0/1,SQL 面答案为准)或「B」(= false/true,布尔类型面答案为准)。裁后:结论写进 #11152 的实施约束,min/max 案例随裁决入列;本卡关闭。

Related: #11152 (carrier of half (a)), #11065 (the avg cell that exposed the family), #11151 (driver-mongodb sibling, on hold).