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* test(engine): pin zero-row cascade delete must not drift an edge table (red) A delete <Node> cascades a delete_where into every incident edge type. The inline delete_where (Dataset::delete) advances Lance HEAD even when zero edges match, but the cascade records the new version only if deleted_rows > 0 — so a node with no incident edges leaves edge:Knows HEAD>manifest drift, which trips the next strict write's ExpectedVersionMismatch and repair refuses it. Red today: edge:Knows manifest=v5, Lance HEAD=v6. Goes green when delete moves to the staged two-phase path (iss-950, Lance 7.0 DeleteBuilder::execute_uncommitted), where a 0-row delete commits no Lance version and the deleted_rows>0 gate becomes correct by construction. * fix(engine): a zero-row delete must not advance Lance HEAD Lance's Dataset::delete commits a new version even when the predicate matches nothing (build_transaction always emits Operation::Delete), so a node delete that cascades a delete_where into an incident edge type with no matching edges advanced that edge table's Lance HEAD while the cascade skipped record_inline (gated on deleted_rows > 0) — leaving HEAD>manifest drift that wedged the next strict write and that repair refused as suspicious/unverifiable. Use Lance 7.0's two-phase DeleteBuilder::execute_uncommitted to read num_deleted_rows before committing: a no-match delete now advances nothing (no version, no drift) and the existing deleted_rows>0 gate is correct by construction. Non-zero deletes commit the staged transaction with skip_auto_cleanup + affected_rows (parity with the prior inline path). First step of the staged-delete migration (iss-950); turns the node_delete_with_no_incident_edges_leaves_no_edge_table_drift regression green. * feat(engine): stage_delete two-phase primitive (MR-A step 0) Add TableStore::stage_delete (Lance 7.0 DeleteBuilder::execute_uncommitted), the two-phase analogue of stage_merge_insert: writes deletion files without advancing Lance HEAD, returns Option<StagedWrite> (None on 0 rows = true no-op), carrying the deletion-vector updated_fragments as new_fragments and the superseded originals as removed_fragment_ids so combine_committed_with_staged makes the deletion visible to in-query reads. No affected_rows is threaded: like stage_merge_insert's Operation::Update commit, the staged delete relies on OmniGraph's per-table write queue + manifest CAS, not Lance's per-dataset conflict resolver (commit_staged is a single attempt). Flip the two residual guards to the staged path: staged_writes.rs now asserts stage_delete does NOT advance HEAD and that a staged delete is read-your-writes visible (the deletion-vector RYW proof D2 retirement depends on); the lance_surface_guards delete guard pins execute_uncommitted's UncommittedDelete. No behavior change yet (callers still use delete_where); Step 1 wires them. * feat(engine): TableStorage::stage_delete + migrate merge delete path (MR-A step 1a) Add stage_delete/Option<StagedHandle> to the TableStorage trait (delegates to TableStore::stage_delete). Migrate the two branch_merge delete sites (three-way RewriteMerged + adopt delta) from the inline delete_where residual to stage_delete + commit_staged — identical in shape to the stage_merge_insert + commit_staged pair above each. HEAD still advances within the merge sequence (via commit_staged), under the unchanged SidecarKind::BranchMerge Phase-B confirmation; the _pre_delete/_pre_index failpoints fire by position, unchanged. merge_truth_table, branching, composite_flow green. * feat(engine): migrate all delete sites to staged path, retire inline delete (MR-A step 1b/1c) Routes every delete through the staged write path so delete never advances Lance HEAD inline — the last inline-commit residual on the mutation path is gone. `MutationStaging` now accumulates delete predicates (`record_delete`) alongside pending write batches; at end-of-query `stage_all` combines a table's predicates into one `(p1) OR (p2) …` `stage_delete` (a deletion-vector transaction, no HEAD advance) and `commit_all` commits it through the same `commit_staged` path as inserts/updates. Deletes are now ordinary staged entries: one sidecar pin at `expected + 1`, no inline special-casing. Migrated callers (all 5): the 3 mutation.rs sites (delete-node, cascade, delete-edge) and the 2 merge.rs sites (already on stage_delete in step 1a). `affected_edges`/`affected` move from post-inline-commit `deleted_rows` to a committed `count_rows` at record time — exact under D₂, bounded by the cascade working set. A predicate matching zero rows stages nothing (the staged equivalent of the old "skip record_inline on 0 deleted rows"), so the zero-row edge-table drift class stays closed by construction. Retired scaffolding now that no caller remains: - `MutationStaging.inline_committed` + `record_inline` → `delete_predicates` + `record_delete`; `StagedMutation.inline_committed`/`paths` fields and all the `commit_all` inline handling (queue keys, sidecar pins with the `record_inline` table_version special-case, the inline recheck loop). - `open_table_for_mutation`'s post-inline-commit reopen branch (deletes no longer advance HEAD mid-query, so a second touch reopens at the pinned version like any write). - `InlineCommitResidual::delete_where` + its `TableStore` impl, the orphaned `TableStore::delete_where`, and `DeleteState`. `InlineCommitResidual` now carries only `create_vector_index` (Lance #6666 still open). D₂ stays for now: staged-delete read-your-writes doesn't yet compose into the pending accumulator (insert-then-delete on one table), so mixed insert/update/delete in one query is still rejected at parse time. Retiring D₂ is step 2. Doc comments updated to match across exec/, storage_layer, db/. Tests (all green): writes, consistency, validators, end_to_end, composite_flow, merge_truth_table, maintenance, recovery, staged_writes, forbidden_apis, lance_surface_guards, changes, point_in_time (286), plus failpoints (63). * docs: delete is a staged write, not an inline-commit residual (MR-A step 1) Update the docs that described `delete` as the inline-commit residual now that MR-A routes it through `stage_delete`. Always-loaded surfaces (AGENTS.md rule 4 / capability matrix, invariants.md Invariant 4 / truth matrix / known gaps) plus the dev write-path docs (writes.md, execution.md incl. its mutation sequence diagram, architecture.md) now state: deletes accumulate as predicates and stage like inserts/updates, no inline HEAD advance; `InlineCommitResidual` carries only `create_vector_index` (Lance #6666). The parse-time D₂ rule is documented as retained — not because delete inline-commits, but because staged-delete read-your-writes is not yet wired into the pending accumulator (MR-A step 2). lance.md's 7.0 audit note marked MR-A as landed. * docs: D₂ is a deliberate boundary, not temporary scaffolding (MR-A close-out) After MR-A staged the delete path, D₂ (a mutation query is insert/update-only OR delete-only) was left framed as temporary — "until Lance ships two-phase delete" / "retire in step 2". Lance shipped that and we used it for the inline-commit fix; D₂'s original justification is gone. It now stands for a different, permanent reason: keeping a query to one kind keeps its read-your-writes unambiguous and each table to one version per query. Retiring it would buy single-commit mixed atomicity (cheap workaround: split, or a branch) at the cost of an in-query delete view, pending pruning, edge id-resolution, and two-commit-per-table ordering in the hot mutation path — complexity not worth earning. Decision: keep D₂ as a deliberate boundary. Reframes the now-stale wording everywhere, no logic change: - The D₂ parse-time error message no longer promises "this restriction lifts when Lance exposes a two-phase delete API"; it states the boundary and points to a branch+merge for one atomic commit. - `enforce_no_mixed_destructive_constructive` doc, AGENTS.md, invariants.md (Invariant 4 / truth matrix / removed from the known-gaps), writes.md, architecture.md, lance.md, and the user mutations doc (which wrongly said deletes "commit through a different path" — both stage now). - Swept remaining stale `delete_where` mentions left from the Step-1 migration: the merge.rs "swap when upstream ships" comments (already swapped), the forbidden_apis / table_ops residual notes, the staged_writes vector-index guard doc (was "same as stage_delete's absence" — stage_delete now exists), and test comments/assert messages in recovery/maintenance/writes/failpoints. Genuinely-historical records (dated Lance audit, rfc-013, bug-case-fix) left. Verified: engine builds warning-free; check-agents-md OK; writes/maintenance/ recovery/staged_writes/forbidden_apis all green. Closes MR-A. * test(engine): overlapping delete predicates must not double-count affected_* (red) Reproduces a reporting regression from the staged-delete migration flagged in PR #308 review. Because deletes now stage (instead of inline-committing), two delete statements in one query both scan the same unchanged committed snapshot; counting each predicate independently over-reports `affected_*` when they overlap. The old inline path committed each delete before the next ran, so it counted distinct. `delete Person where name = "Alice"` then `delete Person where age > 29` over the standard fixture (Alice 30, Charlie 35) removes 2 distinct nodes and 3 distinct edges, but the buggy per-statement counting returns 3 nodes / 6 edges. RED at this commit (asserts left=3, right=2). * fix(engine): dedup overlapping delete predicates when counting affected_* Count each delete statement against the committed snapshot MINUS the predicates a prior delete statement on the same table already recorded: `(pred) AND NOT ((prior1) OR (prior2) …)`. Summed over statements this is inclusion-exclusion — `Σ |pₙ \ (p₁ ∪ …)| = |p₁ ∪ p₂ ∪ …|` — exactly the distinct count the combined `(p1) OR (p2)` staged delete removes. Works for nodes and edges alike with no edge identity needed; the node ID scan uses the same exclusion so a later statement also doesn't re-cascade already-deleted nodes. The ORIGINAL predicate is still what gets recorded (the staged delete removes the union); only the count uses the exclusion. The common single-delete path is unchanged (`prior` empty → filter is just the base predicate). New helper `dedup_delete_filter` + `MutationStaging::recorded_delete_predicates`. Turns the red regression test green (2 nodes / 3 edges); writes (33), end_to_end, validators, maintenance, recovery, composite_flow, merge_truth_table, consistency, changes, and failpoints (63) all stay green. * test(engine): delete dedup must not drop NULL-column rows (red) Follow-up to the overlapping-delete fix flagged in PR #308 review (Greptile P1): the `(base) AND NOT (prior)` exclusion breaks under SQL three-valued logic. If a prior delete predicate references a NULLable column, a later statement's matching row whose column is NULL makes `prior` evaluate to UNKNOWN, `NOT UNKNOWN` is UNKNOWN, and the row is filtered out of the scan — even though the prior delete never matched it. That drops it from `deleted_ids`, skipping its cascade (orphaned edges) or, if it is the only match, leaving the node undeleted. A data bug, not just a miscount. Data: Charlie(age 35), Zoe(age NULL); Knows Zoe→Charlie. `delete Person where age > 30` then `delete Person where name = "Zoe"`. Under the buggy `NOT`, Zoe's scan `(name='Zoe') AND NOT (age>30)` is UNKNOWN → Zoe survives. RED at this commit (Person count left=1, right=0). * fix(engine): NULL-safe delete dedup — exclude only definitely-matched prior rows Change `dedup_delete_filter` from `(base) AND NOT (prior)` to `(base) AND ((prior) IS NOT TRUE)`. `IS NOT TRUE` keeps both FALSE and UNKNOWN rows, so a prior predicate that evaluates to SQL UNKNOWN (a NULL in a referenced column) no longer drops a row this statement legitimately matches — only rows a prior predicate matched as definitely TRUE are excluded from the count/scan. The distinct-count semantics are unchanged for non-NULL data. Turns the red NULL-dedup test green (Zoe deleted, her edge cascaded), and the overlapping-dedup + writes/end_to_end/validators/maintenance/recovery/ composite_flow/consistency suites stay green. * docs(engine): note dedup_delete_filter's load-bearing dependency on D₂ Self-review follow-up: the overlapping-delete dedup assumes the committed snapshot is invariant across a query's statements, which holds only because D₂ forbids mixing writes with deletes (so a delete-touched table has no pending writes). Make that dependency explicit at the function so a future D₂ relaxation is forced to revisit the dedup. Comment-only. * Preserve staged write commit metadata
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2.1 KiB
Markdown
53 lines
2.1 KiB
Markdown
# Mutations
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Write statements live inside a `query` declaration whose body is one or more
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mutation statements (the [query language](../queries/index.md) covers the read
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shape and shared declaration syntax).
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```
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query onboard($name: String, $title: String) {
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insert Person { name: $name, title: $title }
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}
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```
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An edge type is inserted the same way — its endpoint columns are just
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properties in the assignment block (`insert WorksAt { person: $p, org: $o }`).
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## Statements
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- `insert <Type> { prop: <value>, … }`
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- `update <Type> set { prop: <value>, … } where <prop> <op> <value>`
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- `delete <Type> where <prop> <op> <value>`
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`<value>` is a literal, `$param`, or `now()`.
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## Atomicity
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A change query publishes **one commit** at the end of the query. Multiple
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insert/update statements accumulate in memory and commit together — a mid-query
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failure leaves the graph untouched. See [transactions](../branching/transactions.md)
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for the per-query atomicity contract and [branches](../branching/index.md) for
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multi-query workflows.
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## Inserts/updates and deletes cannot mix in one query
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A single change query must be **either insert/update-only or delete-only**.
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Mixing the two is rejected at parse time, before any I/O:
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> `mutation '<name>' on the same query mixes inserts/updates and deletes; split
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> into separate mutations: (1) inserts and updates, then (2) deletes.`
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Run two separate queries instead — the inserts/updates first, then the deletes.
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Each query is still atomic on its own. This is a deliberate rule: inserts,
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updates, and deletes all stage and commit through the same path, but keeping a
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single query to one kind means its read-your-writes stays unambiguous (a read
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within the query never has to reconcile rows you inserted against rows you
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deleted in the same query). If you need the inserts/updates and deletes to land
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as **one** atomic commit, run them on a branch and merge it.
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## Bulk loading
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For loading data from files rather than inline statements, use
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[`omnigraph load`](../cli/index.md) (`--mode overwrite|append|merge`) — it is the
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single bulk-write command and applies the same schema validation and atomic
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publish as inline mutations.
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