Add rescore index type: stores full-precision float vectors in a rowid-keyed
shadow table, quantizes to int8 for fast initial scan, then rescores top
candidates with original vectors. Includes config parser, shadow table
management, insert/delete support, KNN integration, compile flag
(SQLITE_VEC_ENABLE_RESCORE), fuzz targets, and tests.
When a row is deleted from a vec0 virtual table, the rowid slot in
_chunks.rowids and vector data in _vector_chunksNN.vectors are now
zeroed out (previously left as stale data, tracked in #54). When all
rows in a chunk are deleted (validity bitmap all zeros), the chunk and
its associated vector/metadata shadow table rows are reclaimed.
- Add vec0Update_Delete_ClearRowid to zero the rowid blob slot
- Add vec0Update_Delete_ClearVectors to zero all vector blob slots
- Add vec0Update_Delete_DeleteChunkIfEmpty to detect and delete
fully-empty chunks from _chunks, _vector_chunksNN, _metadatachunksNN
- Fix missing rc check in ClearMetadata loop (bug: errors were silently
ignored)
- Fix vec0_new_chunk to explicitly set _rowid_ on shadow table INSERTs
(SHADOW_TABLE_ROWID_QUIRK: "rowid PRIMARY KEY" without INTEGER type
is not a true rowid alias, causing blob_open failures after chunk
delete+recreate cycles)
- Add 13 new tests covering rowid/vector zeroing, chunk reclamation,
metadata/auxiliary/partition/text-PK/int8/bit variants, and
page_count shrinkage verification
- Add vec0-delete-completeness fuzz target
- Update snapshots for new delete zeroing behavior
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
Targeted fuzzer for two-argument vector functions (vec_distance_*,
vec_add, vec_sub) that binds a valid JSON vector as arg1 and fuzz
data as arg2. This exercises the error path in ensure_vector_match()
where the first vector parses successfully (with sqlite3_free cleanup)
but the second fails, triggering the buggy aCleanup(a) call on line
1031 of sqlite-vec.c (should be aCleanup(*a)).
The fuzzer catches this immediately — ASAN reports "bad-free" when
sqlite3_free is called on a stack address.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
