What's wrong
QueryDto represents query state as four independent fields — error: NullOr(String), finishedAt: NullOr(Number), result: NullOr(QueryResultDto), truncated: Boolean (src/glue/api/schemas.ts:255-264). That is 16 representable combinations for 3 real states.
Because the type does not say which is which, the same three-step ladder (finishedAt === null → running; else error !== null → failed; else succeeded) is re-derived in a dozen places:
App.tsx:218, hooks/queries.ts:159,178,182, StatusBar.tsx:38-65 (twice), use-worksheet-messages.ts:31-52, QueryResultContent.tsx:21-42, ResultsPane.tsx:143, mutations.ts:28, use-start-query.ts:37, main/queries/reconcile-queries.ts:17-18, query-runner.ts:139,157,406.
"Canceled" is a first-class state that exists nowhere in the type. It is error === canceledQueryMessage (glue/queries.ts:3, the literal string 'Query canceled.'), compared by string equality at QueryResultContent.tsx:56, and it has genuinely distinct behaviour: a different component branch, span status ok instead of error (tracing/query-traces.ts:32-38), and a suppressed toast (hooks/queries.ts:203).
A symptom worth quoting: QueryResultContent.tsx:30 reads if (query?.error !== undefined && query?.error !== null) — a defensive double-check on a field the contract types as string | null.
Ship this part first (independent, near-zero risk)
The top-level truncated field is dead and duplicated. It is written only as a copy of the nested value (query-runner.ts:410), and every reader uses query.result.truncated instead (use-worksheet-messages.ts:51, StatusBar.tsx:61, ResultsPane.tsx:33). About 10 fixture files have to remember to set a field nothing reads.
Deleting it is a self-contained change and is a prerequisite for the query-list projection fix (see the "query list loads full result sets into memory" issue).
The larger change
Schema.Union on status: 'running' | 'succeeded' | 'failed' | 'canceled', each variant carrying only the fields legal for it. The SQL columns do not change — status is derived in transformQueryRow (query-runner.ts:396-412), the single server-side mapping.
Scope: schemas.ts, 3 producers, ~7 consumers, ~11 test-fixture files. No DB migration.
Risks
mutations.ts:46-49 mutates a TanStack DB draft field-by-field. Under a union this must become a whole-row replace — prototype this first. (Note that the cancel-flow fix in the "cancel is represented twice" issue removes this call site's reason to exist, so doing that one first makes this simpler.)transformQueryRow must stay total for legacy rows, or it re-creates the query-runner.test.ts:258-296 regression where one bad row 400s the entire history list.- Encoding now enforces the correlation, so previously-tolerated contradictions become hard decode failures.
Validation
Existing state coverage is good: query-runner.test.ts:87-95,144-145,188-192,258-296,310-324, use-worksheet-messages.test.ts:62-69,108,116,137, queries.test.tsx:68,83,119.
Add: decode tests rejecting running+result and succeeded+error; a transformQueryRow case per legacy row shape; a list-encode test containing one legacy row.
Found in a codebase-wide simplification audit (F-S01-a). Raised independently by three separate review lanes. Confidence: medium-high on the problem, medium on the full union clearing its migration cost — hence the "ship the deletion first" split.
What's wrong
QueryDtorepresents query state as four independent fields —error: NullOr(String),finishedAt: NullOr(Number),result: NullOr(QueryResultDto),truncated: Boolean(src/glue/api/schemas.ts:255-264). That is 16 representable combinations for 3 real states.Because the type does not say which is which, the same three-step ladder (
finishedAt === null→ running; elseerror !== null→ failed; else succeeded) is re-derived in a dozen places:App.tsx:218,hooks/queries.ts:159,178,182,StatusBar.tsx:38-65(twice),use-worksheet-messages.ts:31-52,QueryResultContent.tsx:21-42,ResultsPane.tsx:143,mutations.ts:28,use-start-query.ts:37,main/queries/reconcile-queries.ts:17-18,query-runner.ts:139,157,406."Canceled" is a first-class state that exists nowhere in the type. It is
error === canceledQueryMessage(glue/queries.ts:3, the literal string'Query canceled.'), compared by string equality atQueryResultContent.tsx:56, and it has genuinely distinct behaviour: a different component branch, span status ok instead of error (tracing/query-traces.ts:32-38), and a suppressed toast (hooks/queries.ts:203).A symptom worth quoting:
QueryResultContent.tsx:30readsif (query?.error !== undefined && query?.error !== null)— a defensive double-check on a field the contract types asstring | null.Ship this part first (independent, near-zero risk)
The top-level
truncatedfield is dead and duplicated. It is written only as a copy of the nested value (query-runner.ts:410), and every reader usesquery.result.truncatedinstead (use-worksheet-messages.ts:51,StatusBar.tsx:61,ResultsPane.tsx:33). About 10 fixture files have to remember to set a field nothing reads.Deleting it is a self-contained change and is a prerequisite for the query-list projection fix (see the "query list loads full result sets into memory" issue).
The larger change
Schema.Uniononstatus: 'running' | 'succeeded' | 'failed' | 'canceled', each variant carrying only the fields legal for it. The SQL columns do not change —statusis derived intransformQueryRow(query-runner.ts:396-412), the single server-side mapping.Scope:
schemas.ts, 3 producers, ~7 consumers, ~11 test-fixture files. No DB migration.Risks
mutations.ts:46-49mutates a TanStack DB draft field-by-field. Under a union this must become a whole-row replace — prototype this first. (Note that the cancel-flow fix in the "cancel is represented twice" issue removes this call site's reason to exist, so doing that one first makes this simpler.)transformQueryRowmust stay total for legacy rows, or it re-creates thequery-runner.test.ts:258-296regression where one bad row 400s the entire history list.Validation
Existing state coverage is good:
query-runner.test.ts:87-95,144-145,188-192,258-296,310-324,use-worksheet-messages.test.ts:62-69,108,116,137,queries.test.tsx:68,83,119.Add: decode tests rejecting
running+resultandsucceeded+error; atransformQueryRowcase per legacy row shape; a list-encode test containing one legacy row.Found in a codebase-wide simplification audit (F-S01-a). Raised independently by three separate review lanes. Confidence: medium-high on the problem, medium on the full union clearing its migration cost — hence the "ship the deletion first" split.