Files
lancedb/docs/web
Xuanwo 725eee8a47 fix: prevent unsafe write retries and bound Blob uploads (#4977)
Ambiguous gateway failures can occur after a write commits, so replaying
the operation can append duplicate rows. Non-idempotent writes now retry
only known precommit failures. Multipart retries reuse the same upload
ID, part ID, and encoded bytes; ambiguous completion returns an
unknown-outcome error without abort or replay. A definite 409/429
completion rejection triggers best-effort cleanup using the call's retry
budget.

Replayable parts and the shared byte-based partition target default to
64 MiB. Dictionary-bearing batches are compacted before size estimation
and again when actual compressed IPC framing requires further splitting:
keys are remapped without changing their types or schema, view backing
buffers are collected, and ListView/LargeListView child ranges are
compacted as an interval union so overlapping views retain sharing.
Parts are prepared on demand; a single row and its schema can still
exceed the target. Multipart progress starts at zero and counts each
acknowledged IPC body once. Rust write builders and Python/TypeScript
`add` expose per-call retry overrides. Atomic `create_table` pre-encodes
to a temporary file and rejects compressed IPC over 256 MiB before
sending any request; the schema-first import guidance now includes
Python, TypeScript, and Rust examples. The shared partition target also
affects local automatic partitioning.

At `cb2a79473bd1b51b950c9fa3e9f247f929c8ac3b`, 70 targeted Rust cases
pass on source verified against the committed four-file patch. With a 16
KiB target and 128 unique 1 KiB dictionary values, the original ordinary
dictionary reproducer drops from 128 requests / 16,942,080 bytes to 16 /
143,488; ListView and LargeListView drop from 128 / 17,056,768 to 16 /
149,632. Encoded HTTP bodies are decoded to check values, nulls, slices,
metadata, changing dictionaries, and overlapping views; additional cases
cover framing-driven splitting, oversized rows, stable retry bytes/IDs,
acknowledged progress, and atomic create. Real HTTP fault tests commit
Blob payloads to a local Lance table and verify byte equality, no
duplicate append, and zero abort/replay after ambiguous completion.

The earlier 811 remote and 7 progress cases at
`f36d217110a25f6b501c0255df9aaa60e3c8000a`, Linux Python remote
database/options results (437 cases plus 8 fixture consumers), Node
retry-binding evidence, and Rust/TypeScript documentation example checks
remain historical validation. Python/Node extensions were not rebuilt
for the dictionary follow-up; these results do not establish current
binding integration or fresh cross-platform/minimum-dependency CI
acceptance.

A separate real Query Node lifecycle experiment used SDK
`b8efe7d2d63647d4962789ca5fc042b59efe073d` and Sophon
`58b7895c7c287810fff4e89f13226fc5fa60d9ef`. After the actual listener
forced a connection closed, a surviving QN accepted a retry with
identical upload ID, part ID, and IPC bytes. Ordinary insert and
complete response-loss scenarios sent no replay or abort; fresh reads
observed exactly one commit and exact Blob bytes in all three scenarios.
This local experiment used a 1-second drain grace, two 32 KiB payloads,
and one distinct staged part. It validates acknowledgement-loss recovery
at those revisions, not concurrent overlapping attempts, large uploads,
physical orphan cleanup, the later dictionary encoding change, or the
original sixth-insert EOF.

The part target is not a process memory limit: source/ancestor buffers
and temporary compaction allocations may coexist. Struct/FixedSizeList
parent nulls can retain hidden child keys; this is not complete
logical-reachability GC for every Arrow combination, and retained hidden
values may affect wire size. The current local Lance 15.0.0-beta.17
rejects ListView/LargeListView persistence; the tests establish remote
client IPC encoding behavior, not native or Cloud persistence support.
Live Cloud, full workspace/Clippy, the original ordinary-insert
disconnect root cause, and Sophon's asynchronous transaction cleanup
behavior are not established. Cancelling during staging retains the
existing server-session cleanup limitation. Function reader delivery is
separate.
2026-11-13 02:05:13 +08:00
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