From ad1212fb3269d1b02f9218deeae506f58f18df07 Mon Sep 17 00:00:00 2001
From: Xuanwo <github@xuanwo.io>
Date: Tue, 27 Oct 2026 17:35:43 +0800
Subject: [PATCH] chore: update Lance to v15.0.0-beta.2 (#4690)

**Blocked on the corrected Lance release:**
https://github.com/lance-format/lance/pull/10370 restores the `Send`
contract required by downstream Function workers. Refresh this upgrade
with that release before merging.

Upgrade the Rust, Java, and Python Lance dependencies to
https://github.com/lance-format/lance/releases/tag/v15.0.0-beta.2. This
brings in bounded vector-index consolidation without retraining
(https://github.com/lance-format/lance/pull/10335) and deletion
filtering for index entries whose fragment coverage was pruned
(https://github.com/lance-format/lance/pull/10325).

Synchronize the vendored `lance-arrow` with the release and retain its
offset-safe validity patch. The existing `nullable_struct_merge`
regression still panics with the unpatched release, so removing that
patch would regress nullable nested queries. Refresh both lockfiles,
including the `zstd-sys` version required by the new Lance encoding
dependency.

Update the custom memtable bitmap test adapter to train on row
addresses, matching the new bitmap contract; remove its obsolete row-ID
conversion.

Preserve the Blob APIs' existing missing-row error messages when newer
Lance rejects a missing fragment earlier in the read path. Retain
upstream attribution in vendored sources while satisfying the repository
license-header check.

Validation of the compatibility fixes: all 58 Rust Blob integration
tests and 219 Python Blob tests pass (one Python test skipped). Strict
workspace Clippy, formatting, and diff checks pass.
---
 Cargo.lock                                  | 163 +++--
 Cargo.toml                                  |  30 +-
 java/pom.xml                                |   2 +-
 python/pyproject.toml                       |   4 +-
 python/uv.lock                              | 202 +++---
 python/vendor/lance-arrow/Cargo.toml        |   5 +-
 python/vendor/lance-arrow/README.lancedb.md |   4 +-
 python/vendor/lance-arrow/src/lib.rs        | 737 ++++++++++++++++++--
 python/vendor/lance-arrow/src/stream.rs     |  93 +--
 rust/lancedb/Cargo.toml                     |   2 +-
 rust/lancedb/src/blob.rs                    |   2 +
 rust/lancedb/src/table/merge.rs             |  20 +-
 12 files changed, 957 insertions(+), 307 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 2844ae735..f189ba871 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -373,7 +373,7 @@ dependencies = [
  "arrow-select",
  "flatbuffers",
  "lz4_flex",
- "zstd",
+ "zstd 0.13.3",
 ]
 
 [[package]]
@@ -3584,8 +3584,8 @@ checksum = "42703706b716c37f96a77aea830392ad231f44c9e9a67872fa5548707e11b11c"
 
 [[package]]
 name = "fsst"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "arrow-array",
  "rand 0.9.5",
@@ -5059,8 +5059,8 @@ checksum = "e037a2e1d8d5fdbd49b16a4ea09d5d6401c1f29eca5ff29d03d3824dba16256a"
 
 [[package]]
 name = "lance"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "arc-swap",
  "arrow",
@@ -5135,7 +5135,7 @@ dependencies = [
 
 [[package]]
 name = "lance-arrow"
-version = "15.0.0-beta.1"
+version = "15.0.0-beta.2"
 dependencies = [
  "arrow-array",
  "arrow-buffer",
@@ -5157,7 +5157,7 @@ dependencies = [
 [[package]]
 name = "lance-arrow-scalar"
 version = "58.0.0"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "arrow-array",
  "arrow-buffer",
@@ -5171,7 +5171,7 @@ dependencies = [
 [[package]]
 name = "lance-arrow-stats"
 version = "58.0.0"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "arrow-array",
  "arrow-schema",
@@ -5180,8 +5180,8 @@ dependencies = [
 
 [[package]]
 name = "lance-bitpacking"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "arrayref",
  "crunchy",
@@ -5191,8 +5191,8 @@ dependencies = [
 
 [[package]]
 name = "lance-core"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "arrow-array",
  "arrow-buffer",
@@ -5229,8 +5229,8 @@ dependencies = [
 
 [[package]]
 name = "lance-datafusion"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "arrow",
  "arrow-array",
@@ -5246,10 +5246,11 @@ dependencies = [
  "datafusion-functions",
  "datafusion-physical-expr",
  "futures",
+ "geodatafusion",
  "half",
  "lance-arrow",
  "lance-core",
- "lance-geo",
+ "lance-datafusion-exec",
  "lance-jsonb",
  "log",
  "pin-project",
@@ -5259,10 +5260,36 @@ dependencies = [
  "tracing",
 ]
 
+[[package]]
+name = "lance-datafusion-exec"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
+dependencies = [
+ "arrow",
+ "arrow-array",
+ "arrow-schema",
+ "async-trait",
+ "datafusion-common",
+ "datafusion-execution",
+ "datafusion-expr",
+ "datafusion-functions",
+ "datafusion-physical-expr",
+ "datafusion-physical-plan",
+ "futures",
+ "half",
+ "lance-arrow",
+ "lance-core",
+ "lance-jsonb",
+ "log",
+ "pin-project",
+ "tokio",
+ "tracing",
+]
+
 [[package]]
 name = "lance-datagen"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "arrow",
  "arrow-array",
@@ -5279,8 +5306,8 @@ dependencies = [
 
 [[package]]
 name = "lance-derive"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -5289,8 +5316,8 @@ dependencies = [
 
 [[package]]
 name = "lance-encoding"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "arrow-arith",
  "arrow-array",
@@ -5315,16 +5342,17 @@ dependencies = [
  "num-traits",
  "prost",
  "prost-build",
+ "serde_json",
  "tokio",
  "tracing",
  "xxhash-rust",
- "zstd",
+ "zstd 0.14.3",
 ]
 
 [[package]]
 name = "lance-file"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "arrow-arith",
  "arrow-array",
@@ -5356,23 +5384,21 @@ dependencies = [
 
 [[package]]
 name = "lance-geo"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
- "datafusion",
  "geo-traits",
  "geo-types",
  "geoarrow-array",
  "geoarrow-schema",
- "geodatafusion",
  "lance-core",
  "serde",
 ]
 
 [[package]]
 name = "lance-index"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "arc-swap",
  "arrow",
@@ -5389,10 +5415,13 @@ dependencies = [
  "blake3",
  "bytes",
  "crossbeam-queue",
- "datafusion",
  "datafusion-common",
+ "datafusion-execution",
  "datafusion-expr",
+ "datafusion-functions",
+ "datafusion-functions-nested",
  "datafusion-physical-expr",
+ "datafusion-physical-plan",
  "dirs",
  "fst",
  "futures",
@@ -5408,7 +5437,7 @@ dependencies = [
  "lance-arrow-stats",
  "lance-bitpacking",
  "lance-core",
- "lance-datafusion",
+ "lance-datafusion-exec",
  "lance-encoding",
  "lance-file",
  "lance-geo",
@@ -5445,16 +5474,16 @@ dependencies = [
 
 [[package]]
 name = "lance-index-core"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "arrow-array",
  "arrow-schema",
  "arrow-select",
  "async-trait",
  "bytes",
- "datafusion",
  "datafusion-common",
+ "datafusion-execution",
  "datafusion-expr",
  "futures",
  "lance-core",
@@ -5469,8 +5498,8 @@ dependencies = [
 
 [[package]]
 name = "lance-io"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "arrow",
  "arrow-array",
@@ -5513,8 +5542,8 @@ dependencies = [
 
 [[package]]
 name = "lance-jsonb"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "byteorder",
  "ethnum",
@@ -5531,8 +5560,8 @@ dependencies = [
 
 [[package]]
 name = "lance-linalg"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "arrow-array",
  "arrow-schema",
@@ -5546,8 +5575,8 @@ dependencies = [
 
 [[package]]
 name = "lance-namespace"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "arrow",
  "async-trait",
@@ -5561,8 +5590,8 @@ dependencies = [
 
 [[package]]
 name = "lance-namespace-impls"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "arc-swap",
  "arrow",
@@ -5616,8 +5645,8 @@ dependencies = [
 
 [[package]]
 name = "lance-select"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "arrow-array",
  "arrow-buffer",
@@ -5631,8 +5660,8 @@ dependencies = [
 
 [[package]]
 name = "lance-table"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "arrow",
  "arrow-array",
@@ -5672,8 +5701,8 @@ dependencies = [
 
 [[package]]
 name = "lance-testing"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "arrow-array",
  "arrow-schema",
@@ -5686,8 +5715,8 @@ dependencies = [
 
 [[package]]
 name = "lance-tokenizer"
-version = "15.0.0-beta.1"
-source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.1#46a7cfe1fba5efa1f90deea4c7b14d414b991409"
+version = "15.0.0-beta.2"
+source = "git+https://github.com/lance-format/lance.git?tag=v15.0.0-beta.2#f50a157269d925ad5708c7b0f7ec6c87b0fd08dd"
 dependencies = [
  "frostem",
  "icu_segmenter",
@@ -7692,7 +7721,7 @@ dependencies = [
  "streaming-iterator",
  "strength_reduce",
  "version_check",
- "zstd",
+ "zstd 0.13.3",
 ]
 
 [[package]]
@@ -12016,7 +12045,16 @@ version = "0.13.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e91ee311a569c327171651566e07972200e76fcfe2242a4fa446149a3881c08a"
 dependencies = [
- "zstd-safe",
+ "zstd-safe 7.2.4",
+]
+
+[[package]]
+name = "zstd"
+version = "0.14.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "db3ae9bf90af6e40197bef767eeefc46ad6397420fe873830bd85e5fbbfb3c70"
+dependencies = [
+ "zstd-safe 8.2.0",
 ]
 
 [[package]]
@@ -12029,10 +12067,19 @@ dependencies = [
 ]
 
 [[package]]
-name = "zstd-sys"
-version = "2.0.16+zstd.1.5.7"
+name = "zstd-safe"
+version = "8.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "91e19ebc2adc8f83e43039e79776e3fda8ca919132d68a1fed6a5faca2683748"
+checksum = "ded520f16b29e1a9b771c722221b2b0a0398c2316d9bb3c42b458a5414d7434b"
+dependencies = [
+ "zstd-sys",
+]
+
+[[package]]
+name = "zstd-sys"
+version = "2.1.2+zstd.1.5.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "481ada9c543b2323cbb7bbdbb5249177fbf0188ed959ed2c15e4b22421c84ed3"
 dependencies = [
  "cc",
  "pkg-config",
diff --git a/Cargo.toml b/Cargo.toml
index 22dec8c0c..40040c329 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -18,21 +18,21 @@ categories = ["database-implementations"]
 rust-version = "1.94.0"
 
 [workspace.dependencies]
-lance = { "version" = "=15.0.0-beta.1", default-features = false, "tag" = "v15.0.0-beta.1", "git" = "https://github.com/lance-format/lance.git" }
-lance-core = { "version" = "=15.0.0-beta.1", "tag" = "v15.0.0-beta.1", "git" = "https://github.com/lance-format/lance.git" }
-lance-datagen = { "version" = "=15.0.0-beta.1", "tag" = "v15.0.0-beta.1", "git" = "https://github.com/lance-format/lance.git" }
-lance-file = { "version" = "=15.0.0-beta.1", "tag" = "v15.0.0-beta.1", "git" = "https://github.com/lance-format/lance.git" }
-lance-io = { "version" = "=15.0.0-beta.1", default-features = false, "tag" = "v15.0.0-beta.1", "git" = "https://github.com/lance-format/lance.git" }
-lance-index = { "version" = "=15.0.0-beta.1", "tag" = "v15.0.0-beta.1", "git" = "https://github.com/lance-format/lance.git" }
-lance-jsonb = { version = "=15.0.0-beta.1", tag = "v15.0.0-beta.1", git = "https://github.com/lance-format/lance.git" }
-lance-linalg = { "version" = "=15.0.0-beta.1", "tag" = "v15.0.0-beta.1", "git" = "https://github.com/lance-format/lance.git" }
-lance-namespace = { "version" = "=15.0.0-beta.1", "tag" = "v15.0.0-beta.1", "git" = "https://github.com/lance-format/lance.git" }
-lance-namespace-impls = { "version" = "=15.0.0-beta.1", default-features = false, "tag" = "v15.0.0-beta.1", "git" = "https://github.com/lance-format/lance.git" }
-lance-table = { "version" = "=15.0.0-beta.1", "tag" = "v15.0.0-beta.1", "git" = "https://github.com/lance-format/lance.git" }
-lance-testing = { "version" = "=15.0.0-beta.1", "tag" = "v15.0.0-beta.1", "git" = "https://github.com/lance-format/lance.git" }
-lance-datafusion = { "version" = "=15.0.0-beta.1", "tag" = "v15.0.0-beta.1", "git" = "https://github.com/lance-format/lance.git" }
-lance-encoding = { "version" = "=15.0.0-beta.1", "tag" = "v15.0.0-beta.1", "git" = "https://github.com/lance-format/lance.git" }
-lance-arrow = { version = "=15.0.0-beta.1", path = "python/vendor/lance-arrow" }
+lance = { "version" = "=15.0.0-beta.2", default-features = false, "tag" = "v15.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-core = { "version" = "=15.0.0-beta.2", "tag" = "v15.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-datagen = { "version" = "=15.0.0-beta.2", "tag" = "v15.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-file = { "version" = "=15.0.0-beta.2", "tag" = "v15.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-io = { "version" = "=15.0.0-beta.2", default-features = false, "tag" = "v15.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-index = { "version" = "=15.0.0-beta.2", "tag" = "v15.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-jsonb = { "version" = "=15.0.0-beta.2", "tag" = "v15.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-linalg = { "version" = "=15.0.0-beta.2", "tag" = "v15.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-namespace = { "version" = "=15.0.0-beta.2", "tag" = "v15.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-namespace-impls = { "version" = "=15.0.0-beta.2", default-features = false, "tag" = "v15.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-table = { "version" = "=15.0.0-beta.2", "tag" = "v15.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-testing = { "version" = "=15.0.0-beta.2", "tag" = "v15.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-datafusion = { "version" = "=15.0.0-beta.2", "tag" = "v15.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-encoding = { "version" = "=15.0.0-beta.2", "tag" = "v15.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
+lance-arrow = { version = "=15.0.0-beta.2", path = "python/vendor/lance-arrow" }
 lancedb = { path = "rust/lancedb", default-features = false }
 ahash = "0.8"
 # Note that this one does not include pyarrow
diff --git a/java/pom.xml b/java/pom.xml
index e3cfb2781..96262a8e9 100644
--- a/java/pom.xml
+++ b/java/pom.xml
@@ -28,7 +28,7 @@
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <arrow.version>15.0.0</arrow.version>
-        <lance-core.version>15.0.0-beta.1</lance-core.version>
+        <lance-core.version>15.0.0-beta.2</lance-core.version>
         <jackson.version>2.18.11</jackson.version>
         <spotless.skip>false</spotless.skip>
         <spotless.version>2.30.0</spotless.version>
diff --git a/python/pyproject.toml b/python/pyproject.toml
index a0de6509c..ac9281248 100644
--- a/python/pyproject.toml
+++ b/python/pyproject.toml
@@ -46,7 +46,7 @@ repository = "https://github.com/lancedb/lancedb"
 [project.optional-dependencies]
 pylance = [
     # Keep the minimum in the bundled Lance major and compatible with tests below.
-    "pylance>=15.0.0b1",
+    "pylance>=15.0.0b2",
 ]
 # A library only needs the OpenTelemetry API; the application supplies and
 # configures the SDK (the actual exporter/reader). See
@@ -64,7 +64,7 @@ tests = [
     "polars>=0.19, <=1.32.3",
     "pyarrow<25",
     "pyarrow-stubs>=16.0",
-    "pylance==15.0.0b1",
+    "pylance==15.0.0b2",
     "requests>=2.31.0",
     "datafusion>=54,<55",
     "opentelemetry-sdk>=1.30.0",
diff --git a/python/uv.lock b/python/uv.lock
index 99bcb439c..329a9ef24 100644
--- a/python/uv.lock
+++ b/python/uv.lock
@@ -1,5 +1,5 @@
 version = 1
-revision = 3
+revision = 5
 requires-python = ">=3.10"
 resolution-markers = [
     "python_full_version >= '3.14' and sys_platform == 'win32'",
@@ -799,7 +799,7 @@ name = "cuda-bindings"
 version = "13.3.1"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
-    { name = "cuda-pathfinder", marker = "(python_full_version < '3.14' and sys_platform == 'emscripten') or (python_full_version < '3.14' and sys_platform == 'win32') or (sys_platform != 'emscripten' and sys_platform != 'win32')" },
+    { name = "cuda-pathfinder" },
 ]
 wheels = [
     { url = "https://files.pythonhosted.org/packages/a9/21/8464d133752951c154feafb3b65c297e7d80f301183d220bec4c830f1441/cuda_bindings-13.3.1-cp310-cp310-manylinux_2_24_aarch64.manylinux_2_28_aarch64.whl", hash = "sha256:120fcc53d57903df529c3486962c56528cba5b7d6c57c99537320ed9922c8b86", size = 6073403, upload-time = "2026-05-29T23:11:36.22Z" },
@@ -834,37 +834,37 @@ wheels = [
 
 [package.optional-dependencies]
 cublas = [
-    { name = "nvidia-cublas", marker = "(python_full_version < '3.14' and sys_platform == 'win32') or sys_platform == 'linux'" },
+    { name = "nvidia-cublas" },
 ]
 cudart = [
-    { name = "nvidia-cuda-runtime", marker = "(python_full_version < '3.14' and sys_platform == 'win32') or sys_platform == 'linux'" },
+    { name = "nvidia-cuda-runtime" },
 ]
 cufft = [
-    { name = "nvidia-cufft", marker = "(python_full_version < '3.14' and sys_platform == 'win32') or sys_platform == 'linux'" },
+    { name = "nvidia-cufft" },
 ]
 cufile = [
-    { name = "nvidia-cufile", marker = "sys_platform == 'linux'" },
+    { name = "nvidia-cufile" },
 ]
 cupti = [
-    { name = "nvidia-cuda-cupti", marker = "(python_full_version < '3.14' and sys_platform == 'win32') or sys_platform == 'linux'" },
+    { name = "nvidia-cuda-cupti" },
 ]
 curand = [
-    { name = "nvidia-curand", marker = "(python_full_version < '3.14' and sys_platform == 'win32') or sys_platform == 'linux'" },
+    { name = "nvidia-curand" },
 ]
 cusolver = [
-    { name = "nvidia-cusolver", marker = "(python_full_version < '3.14' and sys_platform == 'win32') or sys_platform == 'linux'" },
+    { name = "nvidia-cusolver" },
 ]
 cusparse = [
-    { name = "nvidia-cusparse", marker = "(python_full_version < '3.14' and sys_platform == 'win32') or sys_platform == 'linux'" },
+    { name = "nvidia-cusparse" },
 ]
 nvjitlink = [
-    { name = "nvidia-nvjitlink", marker = "(python_full_version < '3.14' and sys_platform == 'win32') or sys_platform == 'linux'" },
+    { name = "nvidia-nvjitlink" },
 ]
 nvrtc = [
-    { name = "nvidia-cuda-nvrtc", marker = "(python_full_version < '3.14' and sys_platform == 'win32') or sys_platform == 'linux'" },
+    { name = "nvidia-cuda-nvrtc" },
 ]
 nvtx = [
-    { name = "nvidia-nvtx", marker = "(python_full_version < '3.14' and sys_platform == 'win32') or sys_platform == 'linux'" },
+    { name = "nvidia-nvtx" },
 ]
 
 [[package]]
@@ -1023,7 +1023,7 @@ name = "exceptiongroup"
 version = "1.3.1"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
-    { name = "typing-extensions", marker = "python_full_version < '3.11'" },
+    { name = "typing-extensions" },
 ]
 sdist = { url = "https://files.pythonhosted.org/packages/50/79/66800aadf48771f6b62f7eb014e352e5d06856655206165d775e675a02c9/exceptiongroup-1.3.1.tar.gz", hash = "sha256:8b412432c6055b0b7d14c310000ae93352ed6754f70fa8f7c34141f91c4e3219", size = 30371, upload-time = "2025-11-21T23:01:54.787Z" }
 wheels = [
@@ -1440,16 +1440,16 @@ resolution-markers = [
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 ]
 dependencies = [
-    { name = "cachetools", marker = "python_full_version < '3.11'" },
-    { name = "certifi", marker = "python_full_version < '3.11'" },
-    { name = "httpx", marker = "python_full_version < '3.11'" },
-    { name = "ibm-cos-sdk", marker = "python_full_version < '3.11'" },
-    { name = "lomond", marker = "python_full_version < '3.11'" },
-    { name = "packaging", marker = "python_full_version < '3.11'" },
-    { name = "pandas", version = "2.2.3", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version < '3.11'" },
-    { name = "requests", marker = "python_full_version < '3.11'" },
-    { name = "tabulate", marker = "python_full_version < '3.11'" },
-    { name = "urllib3", marker = "python_full_version < '3.11'" },
+    { name = "cachetools" },
+    { name = "certifi" },
+    { name = "httpx" },
+    { name = "ibm-cos-sdk" },
+    { name = "lomond" },
+    { name = "packaging" },
+    { name = "pandas", version = "2.2.3", source = { registry = "https://pypi.org/simple" } },
+    { name = "requests" },
+    { name = "tabulate" },
+    { name = "urllib3" },
 ]
 sdist = { url = "https://files.pythonhosted.org/packages/c7/56/2e3df38a1f13062095d7bde23c87a92f3898982993a15186b1bfecbd206f/ibm_watsonx_ai-1.3.42.tar.gz", hash = "sha256:ee5be59009004245d957ce97d1227355516df95a2640189749487614fef674ff", size = 688651, upload-time = "2025-10-01T13:35:41.527Z" }
 wheels = [
@@ -1468,17 +1468,17 @@ resolution-markers = [
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 ]
 dependencies = [
-    { name = "cachetools", marker = "python_full_version >= '3.11'" },
-    { name = "certifi", marker = "python_full_version >= '3.11'" },
-    { name = "httpx", marker = "python_full_version >= '3.11'" },
-    { name = "ibm-cos-sdk", marker = "python_full_version >= '3.11'" },
-    { name = "lomond", marker = "python_full_version >= '3.11'" },
-    { name = "packaging", marker = "python_full_version >= '3.11'" },
-    { name = "pandas", version = "2.3.3", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version >= '3.11' and python_full_version < '3.14'" },
+    { name = "cachetools" },
+    { name = "certifi" },
+    { name = "httpx" },
+    { name = "ibm-cos-sdk" },
+    { name = "lomond" },
+    { name = "packaging" },
+    { name = "pandas", version = "2.3.3", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version < '3.14'" },
     { name = "pandas", version = "3.0.3", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version >= '3.14'" },
-    { name = "requests", marker = "python_full_version >= '3.11'" },
-    { name = "tabulate", marker = "python_full_version >= '3.11'" },
-    { name = "urllib3", marker = "python_full_version >= '3.11'" },
+    { name = "requests" },
+    { name = "tabulate" },
+    { name = "urllib3" },
 ]
 sdist = { url = "https://files.pythonhosted.org/packages/29/a3/c756b534696ab2f3f29882fdb7ca7198b7a5c94e10c0a3a327853d6d6b79/ibm_watsonx_ai-1.5.14.tar.gz", hash = "sha256:a756488bd57e87c0fc51be42dcba871143cfe0ac1e805c497c5047e1e4f13e9d", size = 735804, upload-time = "2026-06-22T12:32:43.85Z" }
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@@ -1554,17 +1554,17 @@ resolution-markers = [
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-    { name = "decorator", marker = "python_full_version < '3.11'" },
-    { name = "exceptiongroup", marker = "python_full_version < '3.11'" },
-    { name = "jedi", marker = "python_full_version < '3.11'" },
-    { name = "matplotlib-inline", marker = "python_full_version < '3.11'" },
-    { name = "pexpect", marker = "python_full_version < '3.11' and sys_platform != 'emscripten' and sys_platform != 'win32'" },
-    { name = "prompt-toolkit", marker = "python_full_version < '3.11'" },
-    { name = "pygments", marker = "python_full_version < '3.11'" },
-    { name = "stack-data", marker = "python_full_version < '3.11'" },
-    { name = "traitlets", marker = "python_full_version < '3.11'" },
-    { name = "typing-extensions", marker = "python_full_version < '3.11'" },
+    { name = "colorama", marker = "sys_platform == 'win32'" },
+    { name = "decorator" },
+    { name = "exceptiongroup" },
+    { name = "jedi" },
+    { name = "matplotlib-inline" },
+    { name = "pexpect", marker = "sys_platform != 'emscripten' and sys_platform != 'win32'" },
+    { name = "prompt-toolkit" },
+    { name = "pygments" },
+    { name = "stack-data" },
+    { name = "traitlets" },
+    { name = "typing-extensions" },
 ]
 sdist = { url = "https://files.pythonhosted.org/packages/40/18/f8598d287006885e7136451fdea0755af4ebcbfe342836f24deefaed1164/ipython-8.39.0.tar.gz", hash = "sha256:4110ae96012c379b8b6db898a07e186c40a2a1ef5d57a7fa83166047d9da7624", size = 5513971, upload-time = "2026-03-27T10:02:13.94Z" }
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@@ -1583,18 +1583,18 @@ resolution-markers = [
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 dependencies = [
-    { name = "colorama", marker = "python_full_version >= '3.11' and sys_platform == 'win32'" },
-    { name = "decorator", marker = "python_full_version >= '3.11'" },
-    { name = "ipython-pygments-lexers", marker = "python_full_version >= '3.11'" },
-    { name = "jedi", marker = "python_full_version >= '3.11'" },
-    { name = "matplotlib-inline", marker = "python_full_version >= '3.11'" },
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-    { name = "prompt-toolkit", marker = "python_full_version >= '3.11'" },
-    { name = "psutil", marker = "python_full_version >= '3.11' and sys_platform != 'cygwin' and sys_platform != 'emscripten'" },
-    { name = "pygments", marker = "python_full_version >= '3.11'" },
-    { name = "stack-data", marker = "python_full_version >= '3.11'" },
-    { name = "traitlets", marker = "python_full_version >= '3.11'" },
-    { name = "typing-extensions", marker = "python_full_version == '3.11.*'" },
+    { name = "colorama", marker = "sys_platform == 'win32'" },
+    { name = "decorator" },
+    { name = "ipython-pygments-lexers" },
+    { name = "jedi" },
+    { name = "matplotlib-inline" },
+    { name = "pexpect", marker = "sys_platform != 'emscripten' and sys_platform != 'win32'" },
+    { name = "prompt-toolkit" },
+    { name = "psutil", marker = "sys_platform != 'cygwin' and sys_platform != 'emscripten'" },
+    { name = "pygments" },
+    { name = "stack-data" },
+    { name = "traitlets" },
+    { name = "typing-extensions", marker = "python_full_version < '3.12'" },
 ]
 sdist = { url = "https://files.pythonhosted.org/packages/53/59/165d3b4d75cc34add3122c4417ecb229085140ac573103c223cd01dde96f/ipython-9.15.0.tar.gz", hash = "sha256:da2819ce2aa83135257df830660b1176d986c3d2876db24df01974fa955b2756", size = 4442580, upload-time = "2026-06-26T11:03:35.913Z" }
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@@ -1606,7 +1606,7 @@ name = "ipython-pygments-lexers"
 version = "1.1.1"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
-    { name = "pygments", marker = "python_full_version >= '3.11'" },
+    { name = "pygments" },
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 sdist = { url = "https://files.pythonhosted.org/packages/ef/4c/5dd1d8af08107f88c7f741ead7a40854b8ac24ddf9ae850afbcf698aa552/ipython_pygments_lexers-1.1.1.tar.gz", hash = "sha256:09c0138009e56b6854f9535736f4171d855c8c08a563a0dcd8022f78355c7e81", size = 8393, upload-time = "2025-01-17T11:24:34.505Z" }
 wheels = [
@@ -1854,9 +1854,9 @@ source = { registry = "https://pypi.org/simple" }
 dependencies = [
     { name = "lance-namespace-urllib3-client" },
 ]
-sdist = { url = "https://files.pythonhosted.org/packages/c0/e7/d5d46594678ee479c0eda830c47b2f5c46133bd100e84e9aa6e01306eca7/lance_namespace-0.13.0.tar.gz", hash = "sha256:24554a0997bdb39595c6e4cb3ac6722069f6cd3bd1a74e7acbba7bfaf774a40d", size = 11636, upload-time = "2026-09-14T02:47:03.871523Z" }
+sdist = { url = "https://files.pythonhosted.org/packages/c0/e7/d5d46594678ee479c0eda830c47b2f5c46133bd100e84e9aa6e01306eca7/lance_namespace-0.13.0.tar.gz", hash = "sha256:24554a0997bdb39595c6e4cb3ac6722069f6cd3bd1a74e7acbba7bfaf774a40d", size = 11636, upload-time = "2026-09-14T02:47:03.871Z" }
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+    { url = "https://files.pythonhosted.org/packages/e7/47/cfa33cca1ba7c749fd2918cfc5c8ded788f378cc6424d23e4fead5a14125/lance_namespace-0.13.0-py3-none-any.whl", hash = "sha256:438c7b17aef421c21c138196e715f2510d62f07e865372047f87c1e75e618c7a", size = 13507, upload-time = "2026-09-14T02:47:01.765Z" },
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 [[package]]
@@ -1869,9 +1869,9 @@ dependencies = [
     { name = "typing-extensions" },
     { name = "urllib3" },
 ]
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+sdist = { url = "https://files.pythonhosted.org/packages/69/25/9aaa4a5e8999693fb0f227c2c0c4b97bd8f0539066408cdff0b89d41b2d5/lance_namespace_urllib3_client-0.13.0.tar.gz", hash = "sha256:1e8a79c6e4e6277033597fd76aa0e2f33d909ca1436c935936e9e569221f43ef", size = 238348, upload-time = "2026-09-14T02:47:04.521Z" }
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+    { url = "https://files.pythonhosted.org/packages/60/4c/7b8f0712a7fe1b8655b711342bc4989696635a79e7027ee56ba3cae23e99/lance_namespace_urllib3_client-0.13.0-py3-none-any.whl", hash = "sha256:fb361eb4f6c7f2d1f9e92809609657b73e38241393e9c4516e12d6b6ee643a0a", size = 406848, upload-time = "2026-09-14T02:47:02.715Z" },
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 [[package]]
@@ -2006,8 +2006,8 @@ requires-dist = [
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     { name = "pyarrow-stubs", marker = "extra == 'tests'", specifier = ">=16.0" },
     { name = "pydantic", specifier = ">=2.7.4,<3" },
-    { name = "pylance", marker = "extra == 'pylance'", specifier = ">=15.0.0b1" },
-    { name = "pylance", marker = "extra == 'tests'", specifier = "==15.0.0b1" },
+    { name = "pylance", marker = "extra == 'pylance'", specifier = ">=15.0.0b2" },
+    { name = "pylance", marker = "extra == 'tests'", specifier = "==15.0.0b2" },
     { name = "pyright", marker = "extra == 'dev'", specifier = ">=1.1.350" },
     { name = "pytest", marker = "extra == 'tests'", specifier = ">=7.0" },
     { name = "pytest-asyncio", marker = "extra == 'tests'", specifier = ">=0.21" },
@@ -2884,7 +2884,7 @@ name = "nvidia-cudnn-cu13"
 version = "9.19.0.56"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
-    { name = "nvidia-cublas", marker = "(python_full_version < '3.14' and sys_platform == 'emscripten') or (python_full_version < '3.14' and sys_platform == 'win32') or (sys_platform != 'emscripten' and sys_platform != 'win32')" },
+    { name = "nvidia-cublas" },
 ]
 wheels = [
     { url = "https://files.pythonhosted.org/packages/f1/84/26025437c1e6b61a707442184fa0c03d083b661adf3a3eecfd6d21677740/nvidia_cudnn_cu13-9.19.0.56-py3-none-manylinux_2_27_aarch64.whl", hash = "sha256:6ed29ffaee1176c612daf442e4dd6cfeb6a0caa43ddcbeb59da94953030b1be4", size = 433781201, upload-time = "2026-02-03T20:40:53.805Z" },
@@ -2896,7 +2896,7 @@ name = "nvidia-cufft"
 version = "12.0.0.61"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
-    { name = "nvidia-nvjitlink", marker = "(python_full_version < '3.14' and sys_platform == 'emscripten') or (python_full_version < '3.14' and sys_platform == 'win32') or (sys_platform != 'emscripten' and sys_platform != 'win32')" },
+    { name = "nvidia-nvjitlink" },
 ]
 wheels = [
     { url = "https://files.pythonhosted.org/packages/8b/ae/f417a75c0259e85c1d2f83ca4e960289a5f814ed0cea74d18c353d3e989d/nvidia_cufft-12.0.0.61-py3-none-manylinux2014_aarch64.manylinux_2_17_aarch64.whl", hash = "sha256:2708c852ef8cd89d1d2068bdbece0aa188813a0c934db3779b9b1faa8442e5f5", size = 214053554, upload-time = "2025-09-04T08:31:38.196Z" },
@@ -2926,9 +2926,9 @@ name = "nvidia-cusolver"
 version = "12.0.4.66"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
-    { name = "nvidia-cublas", marker = "(python_full_version < '3.14' and sys_platform == 'emscripten') or (python_full_version < '3.14' and sys_platform == 'win32') or (sys_platform != 'emscripten' and sys_platform != 'win32')" },
-    { name = "nvidia-cusparse", marker = "(python_full_version < '3.14' and sys_platform == 'emscripten') or (python_full_version < '3.14' and sys_platform == 'win32') or (sys_platform != 'emscripten' and sys_platform != 'win32')" },
-    { name = "nvidia-nvjitlink", marker = "(python_full_version < '3.14' and sys_platform == 'emscripten') or (python_full_version < '3.14' and sys_platform == 'win32') or (sys_platform != 'emscripten' and sys_platform != 'win32')" },
+    { name = "nvidia-cublas" },
+    { name = "nvidia-cusparse" },
+    { name = "nvidia-nvjitlink" },
 ]
 wheels = [
     { url = "https://files.pythonhosted.org/packages/c8/c3/b30c9e935fc01e3da443ec0116ed1b2a009bb867f5324d3f2d7e533e776b/nvidia_cusolver-12.0.4.66-py3-none-manylinux_2_27_aarch64.whl", hash = "sha256:02c2457eaa9e39de20f880f4bd8820e6a1cfb9f9a34f820eb12a155aa5bc92d2", size = 223467760, upload-time = "2025-09-04T08:33:04.222Z" },
@@ -2940,7 +2940,7 @@ name = "nvidia-cusparse"
 version = "12.6.3.3"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
-    { name = "nvidia-nvjitlink", marker = "(python_full_version < '3.14' and sys_platform == 'emscripten') or (python_full_version < '3.14' and sys_platform == 'win32') or (sys_platform != 'emscripten' and sys_platform != 'win32')" },
+    { name = "nvidia-nvjitlink" },
 ]
 wheels = [
     { url = "https://files.pythonhosted.org/packages/f8/94/5c26f33738ae35276672f12615a64bd008ed5be6d1ebcb23579285d960a9/nvidia_cusparse-12.6.3.3-py3-none-manylinux2014_aarch64.manylinux_2_17_aarch64.whl", hash = "sha256:80bcc4662f23f1054ee334a15c72b8940402975e0eab63178fc7e670aa59472c", size = 162155568, upload-time = "2025-09-04T08:33:42.864Z" },
@@ -3117,10 +3117,10 @@ resolution-markers = [
     "python_full_version < '3.11'",
 ]
 dependencies = [
-    { name = "numpy", version = "2.2.6", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version < '3.11'" },
-    { name = "python-dateutil", marker = "python_full_version < '3.11'" },
-    { name = "pytz", marker = "python_full_version < '3.11'" },
-    { name = "tzdata", marker = "python_full_version < '3.11'" },
+    { name = "numpy", version = "2.2.6", source = { registry = "https://pypi.org/simple" } },
+    { name = "python-dateutil" },
+    { name = "pytz" },
+    { name = "tzdata" },
 ]
 sdist = { url = "https://files.pythonhosted.org/packages/9c/d6/9f8431bacc2e19dca897724cd097b1bb224a6ad5433784a44b587c7c13af/pandas-2.2.3.tar.gz", hash = "sha256:4f18ba62b61d7e192368b84517265a99b4d7ee8912f8708660fb4a366cc82667", size = 4399213, upload-time = "2024-09-20T13:10:04.827Z" }
 wheels = [
@@ -3169,11 +3169,11 @@ resolution-markers = [
     "python_full_version == '3.11.*'",
 ]
 dependencies = [
-    { name = "numpy", version = "2.4.6", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version == '3.11.*'" },
+    { name = "numpy", version = "2.4.6", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version < '3.12' or python_full_version >= '3.14'" },
     { name = "numpy", version = "2.5.1", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version >= '3.12' and python_full_version < '3.14'" },
-    { name = "python-dateutil", marker = "python_full_version >= '3.11' and python_full_version < '3.14'" },
-    { name = "pytz", marker = "python_full_version >= '3.11' and python_full_version < '3.14'" },
-    { name = "tzdata", marker = "python_full_version >= '3.11' and python_full_version < '3.14'" },
+    { name = "python-dateutil" },
+    { name = "pytz" },
+    { name = "tzdata" },
 ]
 sdist = { url = "https://files.pythonhosted.org/packages/33/01/d40b85317f86cf08d853a4f495195c73815fdf205eef3993821720274518/pandas-2.3.3.tar.gz", hash = "sha256:e05e1af93b977f7eafa636d043f9f94c7ee3ac81af99c13508215942e64c993b", size = 4495223, upload-time = "2025-09-29T23:34:51.853Z" }
 wheels = [
@@ -3236,9 +3236,9 @@ resolution-markers = [
     "python_full_version >= '3.14' and sys_platform != 'emscripten' and sys_platform != 'win32'",
 ]
 dependencies = [
-    { name = "numpy", version = "2.5.1", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version >= '3.14'" },
-    { name = "python-dateutil", marker = "python_full_version >= '3.14'" },
-    { name = "tzdata", marker = "(python_full_version >= '3.14' and sys_platform == 'emscripten') or (python_full_version >= '3.14' and sys_platform == 'win32')" },
+    { name = "numpy", version = "2.5.1", source = { registry = "https://pypi.org/simple" } },
+    { name = "python-dateutil" },
+    { name = "tzdata", marker = "sys_platform == 'emscripten' or sys_platform == 'win32'" },
 ]
 sdist = { url = "https://files.pythonhosted.org/packages/f8/87/4341c6252d1c47b08768c3d25ac487362bf403f0313ddae4a2a26c9b1b4c/pandas-3.0.3.tar.gz", hash = "sha256:696a4a00a2a2a35d4e5deb3fc946641b96c944f02230e4f76137fe35d806c4fc", size = 4651414, upload-time = "2026-05-11T18:54:29.21Z" }
 wheels = [
@@ -3346,7 +3346,7 @@ name = "pexpect"
 version = "4.9.0"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
-    { name = "ptyprocess", marker = "(python_full_version < '3.14' and sys_platform == 'emscripten') or (python_full_version < '3.14' and sys_platform == 'win32') or (sys_platform != 'emscripten' and sys_platform != 'win32')" },
+    { name = "ptyprocess" },
 ]
 sdist = { url = "https://files.pythonhosted.org/packages/42/92/cc564bf6381ff43ce1f4d06852fc19a2f11d180f23dc32d9588bee2f149d/pexpect-4.9.0.tar.gz", hash = "sha256:ee7d41123f3c9911050ea2c2dac107568dc43b2d3b0c7557a33212c398ead30f", size = 166450, upload-time = "2023-11-25T09:07:26.339Z" }
 wheels = [
@@ -3938,7 +3938,7 @@ crypto = [
 
 [[package]]
 name = "pylance"
-version = "15.0.0b1"
+version = "15.0.0b2"
 source = { registry = "https://pypi.fury.io/lance-format/" }
 dependencies = [
     { name = "lance-namespace" },
@@ -3948,12 +3948,12 @@ dependencies = [
     { name = "pyarrow" },
 ]
 wheels = [
-    { url = "https://pypi.fury.io/lance-format/-/ver_23L1Nd/pylance-15.0.0b1-cp310-abi3-macosx_11_0_arm64.whl", hash = "sha256:19605d3daca1224cc0db079054be5d4eec403dcf286bf4617430bfc259ab0a52" },
-    { url = "https://pypi.fury.io/lance-format/-/ver_1Ho3RK/pylance-15.0.0b1-cp310-abi3-manylinux_2_17_aarch64.manylinux2014_aarch64.whl", hash = "sha256:be22b0b6f1e1d250ffaa82b449e982c817db33103c483d1005020285310623cf" },
-    { url = "https://pypi.fury.io/lance-format/-/ver_1QmyF0/pylance-15.0.0b1-cp310-abi3-manylinux_2_17_x86_64.manylinux2014_x86_64.whl", hash = "sha256:a5b2761d60b1b9db112058213f1f7b2de82b08cbe65888fab08b0a56e702482e" },
-    { url = "https://pypi.fury.io/lance-format/-/ver_1in2Ph/pylance-15.0.0b1-cp310-abi3-manylinux_2_28_aarch64.whl", hash = "sha256:294a0fedae312ed32d1b66cddbf7e69770ec9b4c82a873af60c619ed88450718" },
-    { url = "https://pypi.fury.io/lance-format/-/ver_21xpLH/pylance-15.0.0b1-cp310-abi3-manylinux_2_28_x86_64.whl", hash = "sha256:ff20a16703d4d3f3bc675b25ce1871ba1d54137929dc46305bffdd07f7b35a6b" },
-    { url = "https://pypi.fury.io/lance-format/-/ver_AAGzF/pylance-15.0.0b1-cp310-abi3-win_amd64.whl", hash = "sha256:3b134e24a5becfc940ca134cf78aa3bae8b80ec40f8927a1b856273ab76213f2" },
+    { url = "https://pypi.fury.io/lance-format/-/ver_5aLfR/pylance-15.0.0b2-cp310-abi3-macosx_11_0_arm64.whl", hash = "sha256:fd6b872e348d804c3188d014f2ff469f8cfaff5bbe846617e665c1e2a2965683" },
+    { url = "https://pypi.fury.io/lance-format/-/ver_1W21Yj/pylance-15.0.0b2-cp310-abi3-manylinux_2_17_aarch64.manylinux2014_aarch64.whl", hash = "sha256:b0ed217ee71bea57ef97303bd1318ae212ee005c885c16390d7efbaf1f7398e3" },
+    { url = "https://pypi.fury.io/lance-format/-/ver_12xJCp/pylance-15.0.0b2-cp310-abi3-manylinux_2_17_x86_64.manylinux2014_x86_64.whl", hash = "sha256:72580d6359db4d471c578daab46a35fd87e74e57a1cb64e333188fea1e1c2f1b" },
+    { url = "https://pypi.fury.io/lance-format/-/ver_m4ypB/pylance-15.0.0b2-cp310-abi3-manylinux_2_28_aarch64.whl", hash = "sha256:c194f95e2d2b1c5a9e4f57ed2681a9295effe5aaa165bf924f2b2090094c4645" },
+    { url = "https://pypi.fury.io/lance-format/-/ver_1zYkf2/pylance-15.0.0b2-cp310-abi3-manylinux_2_28_x86_64.whl", hash = "sha256:c14532517ed1452d9cb215f33dc4bc3166500e14145c8c6f2f3538b82ac5147b" },
+    { url = "https://pypi.fury.io/lance-format/-/ver_xp2do/pylance-15.0.0b2-cp310-abi3-win_amd64.whl", hash = "sha256:ce13e573a1842eda18f9b74eec4c8d1dc60db0895581db3226c6a6b1a8e79a75" },
 ]
 
 [[package]]
@@ -4709,10 +4709,10 @@ resolution-markers = [
     "python_full_version < '3.11'",
 ]
 dependencies = [
-    { name = "joblib", marker = "python_full_version < '3.11'" },
-    { name = "numpy", version = "2.2.6", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version < '3.11'" },
-    { name = "scipy", version = "1.15.3", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version < '3.11'" },
-    { name = "threadpoolctl", marker = "python_full_version < '3.11'" },
+    { name = "joblib" },
+    { name = "numpy", version = "2.2.6", source = { registry = "https://pypi.org/simple" } },
+    { name = "scipy", version = "1.15.3", source = { registry = "https://pypi.org/simple" } },
+    { name = "threadpoolctl" },
 ]
 sdist = { url = "https://files.pythonhosted.org/packages/98/c2/a7855e41c9d285dfe86dc50b250978105dce513d6e459ea66a6aeb0e1e0c/scikit_learn-1.7.2.tar.gz", hash = "sha256:20e9e49ecd130598f1ca38a1d85090e1a600147b9c02fa6f15d69cb53d968fda", size = 7193136, upload-time = "2025-09-09T08:21:29.075Z" }
 wheels = [
@@ -4760,13 +4760,13 @@ resolution-markers = [
     "python_full_version == '3.11.*'",
 ]
 dependencies = [
-    { name = "joblib", marker = "python_full_version >= '3.11'" },
-    { name = "narwhals", marker = "python_full_version >= '3.11'" },
-    { name = "numpy", version = "2.4.6", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version == '3.11.*'" },
+    { name = "joblib" },
+    { name = "narwhals" },
+    { name = "numpy", version = "2.4.6", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version < '3.12'" },
     { name = "numpy", version = "2.5.1", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version >= '3.12'" },
-    { name = "scipy", version = "1.17.1", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version == '3.11.*'" },
+    { name = "scipy", version = "1.17.1", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version < '3.12'" },
     { name = "scipy", version = "1.18.0", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version >= '3.12'" },
-    { name = "threadpoolctl", marker = "python_full_version >= '3.11'" },
+    { name = "threadpoolctl" },
 ]
 sdist = { url = "https://files.pythonhosted.org/packages/fa/6f/37092bdb25f712817231799fc5674d8e704066a8a70c1d2d40517e18b4ab/scikit_learn-1.9.0.tar.gz", hash = "sha256:8833266989d3a5110178a9fae30783675460724d0e1efb13b14901d2c660c557", size = 7750767, upload-time = "2026-06-02T11:54:32.706Z" }
 wheels = [
@@ -4810,7 +4810,7 @@ resolution-markers = [
     "python_full_version < '3.11'",
 ]
 dependencies = [
-    { name = "numpy", version = "2.2.6", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version < '3.11'" },
+    { name = "numpy", version = "2.2.6", source = { registry = "https://pypi.org/simple" } },
 ]
 sdist = { url = "https://files.pythonhosted.org/packages/0f/37/6964b830433e654ec7485e45a00fc9a27cf868d622838f6b6d9c5ec0d532/scipy-1.15.3.tar.gz", hash = "sha256:eae3cf522bc7df64b42cad3925c876e1b0b6c35c1337c93e12c0f366f55b0eaf", size = 59419214, upload-time = "2025-05-08T16:13:05.955Z" }
 wheels = [
@@ -4869,7 +4869,7 @@ resolution-markers = [
     "python_full_version == '3.11.*'",
 ]
 dependencies = [
-    { name = "numpy", version = "2.4.6", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version == '3.11.*'" },
+    { name = "numpy", version = "2.4.6", source = { registry = "https://pypi.org/simple" } },
 ]
 sdist = { url = "https://files.pythonhosted.org/packages/7a/97/5a3609c4f8d58b039179648e62dd220f89864f56f7357f5d4f45c29eb2cc/scipy-1.17.1.tar.gz", hash = "sha256:95d8e012d8cb8816c226aef832200b1d45109ed4464303e997c5b13122b297c0", size = 30573822, upload-time = "2026-02-23T00:26:24.851Z" }
 wheels = [
@@ -4946,7 +4946,7 @@ resolution-markers = [
     "python_full_version >= '3.12' and python_full_version < '3.14'",
 ]
 dependencies = [
-    { name = "numpy", version = "2.5.1", source = { registry = "https://pypi.org/simple" }, marker = "python_full_version >= '3.12'" },
+    { name = "numpy", version = "2.5.1", source = { registry = "https://pypi.org/simple" } },
 ]
 sdist = { url = "https://files.pythonhosted.org/packages/a7/25/c2700dfaf6442b4effaa91af24ebce5dc9d31bb4a69706313aae70d72cd0/scipy-1.18.0.tar.gz", hash = "sha256:67b2ad2ad54c72ca6d04975a9b2df8c3638c34ddd5b28738e94fc2b57929d378", size = 30774447, upload-time = "2026-06-19T15:01:43.456Z" }
 wheels = [
diff --git a/python/vendor/lance-arrow/Cargo.toml b/python/vendor/lance-arrow/Cargo.toml
index 9cb156f2e..e9adc478c 100644
--- a/python/vendor/lance-arrow/Cargo.toml
+++ b/python/vendor/lance-arrow/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "lance-arrow"
-version = "15.0.0-beta.1"
+version = "15.0.0-beta.2"
 edition = "2024"
 authors = ["Lance Devs <dev@lance.org>"]
 license = "Apache-2.0"
@@ -10,9 +10,6 @@ description = "Arrow Extension for Lance"
 keywords = ["data-format", "data-science", "machine-learning", "apache-arrow", "data-analytics"]
 categories = ["database-implementations"]
 
-[lib]
-crate-type = ["cdylib", "rlib"]
-
 [dependencies]
 arrow-array.workspace = true
 arrow-buffer.workspace = true
diff --git a/python/vendor/lance-arrow/README.lancedb.md b/python/vendor/lance-arrow/README.lancedb.md
index 5ed714e08..4a9f6176f 100644
--- a/python/vendor/lance-arrow/README.lancedb.md
+++ b/python/vendor/lance-arrow/README.lancedb.md
@@ -1,5 +1,5 @@
-This directory contains `rust/lance-arrow` from Lance tag `v15.0.0-beta.1`
-(commit `46a7cfe1fba5efa1f90deea4c7b14d414b991409`), licensed under Apache-2.0.
+This directory contains `rust/lance-arrow` from Lance tag `v15.0.0-beta.2`
+(commit `f50a157269d925ad5708c7b0f7ec6c87b0fd08dd`), licensed under Apache-2.0.
 
 LanceDB carries a local fix in `src/lib.rs` for sliced child validity bitmaps
 until a Lance release includes the fix. The patch is selected in the root
diff --git a/python/vendor/lance-arrow/src/lib.rs b/python/vendor/lance-arrow/src/lib.rs
index f26e1f3e3..6c31cf0c5 100644
--- a/python/vendor/lance-arrow/src/lib.rs
+++ b/python/vendor/lance-arrow/src/lib.rs
@@ -27,7 +27,7 @@ use arrow_array::{
 use arrow_array::{
     Float32Array, Float64Array, Int8Array, Int16Array, Int32Array, Int64Array, new_null_array,
 };
-use arrow_buffer::MutableBuffer;
+use arrow_buffer::{BooleanBufferBuilder, MutableBuffer, NullBuffer};
 use arrow_data::ArrayDataBuilder;
 use arrow_schema::{ArrowError, DataType, Field, Fields, IntervalUnit, Schema, SortOptions};
 use arrow_select::{interleave::interleave, take::take};
@@ -670,7 +670,7 @@ impl RecordBatchExt for RecordBatch {
         }
         let left_struct_array: StructArray = self.clone().into();
         let right_struct_array: StructArray = other.clone().into();
-        self.try_new_from_struct_array(merge(&left_struct_array, &right_struct_array))
+        self.try_new_from_struct_array(merge(&left_struct_array, &right_struct_array)?)
     }
 
     fn merge_with_schema(&self, other: &RecordBatch, schema: &Schema) -> Result<RecordBatch> {
@@ -921,12 +921,44 @@ fn holds_struct(data_type: &DataType) -> bool {
     }
 }
 
+/// The values of `list`, with the items of every entry that is null in `list`
+/// but valid in `other` made null. Those entries become valid when the two
+/// lists are merged, and their items here were never meant to be read. Merging
+/// the items then pushes these nulls into their children.
+fn hide_items_revealed_by<T: OffsetSizeTrait>(
+    list: &GenericListArray<T>,
+    other: Option<&NullBuffer>,
+) -> ArrayRef {
+    let Some(nulls) = list.nulls() else {
+        return list.values().clone();
+    };
+    let revealed = match other {
+        Some(other) => other.inner() & &!nulls.inner(),
+        None => !nulls.inner(),
+    };
+    if revealed.count_set_bits() == 0 {
+        return list.values().clone();
+    }
+    let offsets = list.value_offsets();
+    let mut items_validity = BooleanBufferBuilder::new(list.values().len());
+    items_validity.append_n(list.values().len(), true);
+    for row in revealed.set_indices() {
+        for item in offsets[row].as_usize()..offsets[row + 1].as_usize() {
+            items_validity.set_bit(item, false);
+        }
+    }
+    adjust_child_validity(
+        list.values(),
+        Some(&NullBuffer::new(items_validity.finish())),
+    )
+}
+
 /// Merge the values of two lists: structs field by field, nested lists
 /// recursively, anything else keeps the left side.
-fn merge_list_values(left: &ArrayRef, right: &ArrayRef) -> ArrayRef {
-    match (left.data_type(), right.data_type()) {
+fn merge_list_values(left: &ArrayRef, right: &ArrayRef) -> Result<ArrayRef> {
+    Ok(match (left.data_type(), right.data_type()) {
         (DataType::Struct(_), DataType::Struct(_)) => {
-            Arc::new(merge(left.as_struct(), right.as_struct()))
+            Arc::new(merge(left.as_struct(), right.as_struct())?)
         }
         (DataType::List(_), DataType::List(_))
         | (DataType::LargeList(_), DataType::LargeList(_))
@@ -934,27 +966,29 @@ fn merge_list_values(left: &ArrayRef, right: &ArrayRef) -> ArrayRef {
                 && holds_struct(left.data_type())
                 && holds_struct(right.data_type()) =>
         {
-            merge_list_struct(left, right)
+            merge_list_struct(left, right, None, None)?
         }
         _ => left.clone(),
-    }
+    })
 }
 
 fn merge_list_struct_helper<T: OffsetSizeTrait>(
     left: &dyn Array,
     right: &dyn Array,
-) -> Arc<dyn Array> {
+    null_left: bool,
+    null_right: bool,
+) -> Result<ArrayRef> {
     let left_list: &GenericListArray<T> = left.as_list();
     let right_list: &GenericListArray<T> = right.as_list();
-    let item_name = match left.data_type() {
-        DataType::List(item) | DataType::LargeList(item) => item.name().clone(),
-        _ => unreachable!(),
+    let ((DataType::List(left_item), DataType::List(right_item))
+    | (DataType::LargeList(left_item), DataType::LargeList(right_item))) =
+        (left.data_type(), right.data_type())
+    else {
+        unreachable!()
     };
-    // One side all-null (a placeholder for columns this fragment lacks) has
-    // no values, so stand in nulls shaped like the other side's.
-    let null_left = left_list.null_count() == left_list.len();
-    let null_right = !null_left && right_list.null_count() == right_list.len();
-    let (merged_items, list, items_nullable) = if null_left || null_right {
+    let (merged_items, list, nulls, items_nullable) = if null_left || null_right {
+        // One side all-null (a placeholder for columns this fragment lacks) has
+        // no values, so stand in nulls shaped like the other side's.
         let not_null = if null_left { right_list } else { left_list };
         let values_len = not_null.values().len();
         let values = |list: &GenericListArray<T>, is_null: bool| {
@@ -967,39 +1001,68 @@ fn merge_list_struct_helper<T: OffsetSizeTrait>(
         let merged = merge_list_values(
             &values(left_list, null_left),
             &values(right_list, null_right),
-        );
-        (merged, not_null, true)
+        )?;
+        (
+            merged,
+            not_null,
+            not_null.nulls().cloned(),
+            left_item.is_nullable() || right_item.is_nullable(),
+        )
     } else {
         if left_list.offsets().inner() != right_list.offsets().inner() {
             panic!("Attempt to merge list struct arrays which do not have same offsets");
         }
-        let merged = merge_list_values(left_list.values(), right_list.values());
-        let nullable = match left.data_type() {
-            DataType::List(item) | DataType::LargeList(item) => item.is_nullable(),
-            _ => unreachable!(),
-        };
-        (merged, left_list, nullable)
+        // The lists share offsets, and an entry is valid if either side has it,
+        // as for struct rows. Each side's items under its own null entries are
+        // hidden first, so the other side's validity cannot expose them.
+        let left_items = hide_items_revealed_by(left_list, right_list.nulls());
+        let right_items = hide_items_revealed_by(right_list, left_list.nulls());
+        let merged = merge_list_values(&left_items, &right_items)?;
+        (
+            merged,
+            left_list,
+            merge_struct_validity(left_list.nulls(), right_list.nulls()),
+            left_item.is_nullable() || right_item.is_nullable(),
+        )
     };
     let items_field = Arc::new(Field::new(
-        item_name,
+        left_item.name(),
         merged_items.data_type().clone(),
         items_nullable,
     ));
-    Arc::new(GenericListArray::<T>::new(
+    Ok(Arc::new(GenericListArray::<T>::new(
         items_field,
         list.offsets().clone(),
         merged_items,
-        list.nulls().cloned(),
-    ))
+        nulls,
+    )))
 }
 
 /// Merge two lists whose items hold structs. Only succeeds if both lists have
 /// the same offsets or one of them is all-null; panics otherwise.
-fn merge_list_struct(left: &dyn Array, right: &dyn Array) -> Arc<dyn Array> {
+///
+/// `left_parent` and `right_parent`, when given, null each side's entries under
+/// its null parent rows before the merge.
+fn merge_list_struct(
+    left: &ArrayRef,
+    right: &ArrayRef,
+    left_parent: Option<&NullBuffer>,
+    right_parent: Option<&NullBuffer>,
+) -> Result<ArrayRef> {
+    // The parents are applied before the all-null side is picked, so a side
+    // whose rows all sit under null parents counts as the placeholder and the
+    // other side's offsets are kept.
+    let left = adjust_child_validity(left, left_parent);
+    let right = adjust_child_validity(right, right_parent);
+    let null_left = left.null_count() == left.len();
+    let null_right = !null_left && right.null_count() == right.len();
+    let (left, right) = (left.as_ref(), right.as_ref());
     match (left.data_type(), right.data_type()) {
-        (DataType::List(_), DataType::List(_)) => merge_list_struct_helper::<i32>(left, right),
+        (DataType::List(_), DataType::List(_)) => {
+            merge_list_struct_helper::<i32>(left, right, null_left, null_right)
+        }
         (DataType::LargeList(_), DataType::LargeList(_)) => {
-            merge_list_struct_helper::<i64>(left, right)
+            merge_list_struct_helper::<i64>(left, right, null_left, null_right)
         }
         _ => unreachable!(),
     }
@@ -1187,7 +1250,46 @@ fn adjust_child_validity(
     )
 }
 
-fn merge(left_struct_array: &StructArray, right_struct_array: &StructArray) -> StructArray {
+/// Fails if `field`, a non-nullable child of one side's struct, sits under a
+/// row that is null on that side but valid in `merged`. The merged row is valid
+/// because the other side has it, and this side has no value to show there.
+fn check_hideable(
+    field: &Field,
+    parent: Option<&NullBuffer>,
+    merged: Option<&NullBuffer>,
+) -> Result<()> {
+    let Some(parent) = parent.filter(|_| !field.is_nullable()) else {
+        return Ok(());
+    };
+    let revealed = match merged {
+        Some(merged) => merged.inner() & &!parent.inner(),
+        None => !parent.inner(),
+    };
+    match revealed.set_indices().next() {
+        None => Ok(()),
+        Some(row) => Err(ArrowError::InvalidArgumentError(format!(
+            "Cannot merge non-nullable field '{}': its parent is null on one side but valid \
+             on the other at row {row}, where the field has no value",
+            field.name()
+        ))),
+    }
+}
+
+/// `column`, a child of one side's struct, with that struct's null rows pushed
+/// into it. The merged struct is valid where either side is, so the column
+/// would otherwise show, at a row only the other side has, what its own null
+/// parent hides.
+fn hide_under_parent(
+    field: &Field,
+    column: &ArrayRef,
+    parent: Option<&NullBuffer>,
+    merged: Option<&NullBuffer>,
+) -> Result<ArrayRef> {
+    check_hideable(field, parent, merged)?;
+    Ok(adjust_child_validity(column, parent))
+}
+
+fn merge(left_struct_array: &StructArray, right_struct_array: &StructArray) -> Result<StructArray> {
     let mut fields: Vec<Field> = vec![];
     let mut columns: Vec<ArrayRef> = vec![];
     let right_fields = right_struct_array.fields();
@@ -1199,6 +1301,7 @@ fn merge(left_struct_array: &StructArray, right_struct_array: &StructArray) -> S
 
     // Compute merged validity
     let merged_validity = merge_struct_validity(left_validity, right_validity);
+    let merged = merged_validity.as_ref();
 
     // iterate through the fields on the left hand side
     for (left_field, left_column) in left_struct_array
@@ -1217,9 +1320,13 @@ fn merge(left_struct_array: &StructArray, right_struct_array: &StructArray) -> S
                 // if both fields are struct, merge them recursively
                 match (left_field.data_type(), right_field.data_type()) {
                     (DataType::Struct(_), DataType::Struct(_)) => {
-                        let left_sub_array = left_column.as_struct();
-                        let right_sub_array = right_column.as_struct();
-                        let merged_sub_array = merge(left_sub_array, right_sub_array);
+                        // Both sides feed this column, so a row one side's parent
+                        // hides can still take its value from the other side, and
+                        // the field's nullability is checked on the merged result.
+                        let left_sub_array = adjust_child_validity(left_column, left_validity);
+                        let right_sub_array = adjust_child_validity(right_column, right_validity);
+                        let merged_sub_array =
+                            merge(left_sub_array.as_struct(), right_sub_array.as_struct())?;
                         fields.push(Field::new(
                             left_field.name(),
                             merged_sub_array.data_type().clone(),
@@ -1235,12 +1342,22 @@ fn merge(left_struct_array: &StructArray, right_struct_array: &StructArray) -> S
                         // Identical inner types: nothing to merge, keep the left column.
                         if left_list.data_type() == right_list.data_type() {
                             fields.push(left_field.as_ref().clone());
-                            columns.push(left_column.clone());
+                            columns.push(hide_under_parent(
+                                left_field,
+                                left_column,
+                                left_validity,
+                                merged,
+                            )?);
                         } else {
                             // The struct fields differ, so merge them structurally. merge_list_struct
                             // only succeeds when both lists share offsets or one side is all-null;
                             // it panics otherwise.
-                            let merged_sub_array = merge_list_struct(&left_column, &right_column);
+                            let merged_sub_array = merge_list_struct(
+                                left_column,
+                                right_column,
+                                left_validity,
+                                right_validity,
+                            )?;
 
                             fields.push(Field::new(
                                 left_field.name(),
@@ -1254,41 +1371,41 @@ fn merge(left_struct_array: &StructArray, right_struct_array: &StructArray) -> S
                     _ => {
                         // TODO handle list-of-struct and other types
                         fields.push(left_field.as_ref().clone());
-                        // Adjust the column validity: if left struct was null, propagate to child
-                        let adjusted_column = adjust_child_validity(left_column, left_validity);
-                        columns.push(adjusted_column);
+                        columns.push(hide_under_parent(
+                            left_field,
+                            left_column,
+                            left_validity,
+                            merged,
+                        )?);
                     }
                 }
             }
             None => {
                 fields.push(left_field.as_ref().clone());
-                // Adjust the column validity: if left struct was null, propagate to child
-                let adjusted_column = adjust_child_validity(left_column, left_validity);
-                columns.push(adjusted_column);
+                columns.push(hide_under_parent(
+                    left_field,
+                    left_column,
+                    left_validity,
+                    merged,
+                )?);
             }
         }
     }
 
     // now iterate through the fields on the right hand side
-    right_fields
-        .iter()
-        .zip(right_columns.iter())
-        .for_each(|(field, column)| {
-            // add new columns on the right
-            if !left_struct_array
-                .fields()
-                .iter()
-                .any(|f| f.name() == field.name())
-            {
-                fields.push(field.as_ref().clone());
-                // This field doesn't exist on the left
-                // We use the right's column but need to adjust for struct validity
-                let adjusted_column = adjust_child_validity(column, right_validity);
-                columns.push(adjusted_column);
-            }
-        });
+    for (field, column) in right_fields.iter().zip(right_columns.iter()) {
+        // add new columns on the right
+        if !left_struct_array
+            .fields()
+            .iter()
+            .any(|f| f.name() == field.name())
+        {
+            fields.push(field.as_ref().clone());
+            columns.push(hide_under_parent(field, column, right_validity, merged)?);
+        }
+    }
 
-    StructArray::try_new(Fields::from(fields), columns, merged_validity).unwrap()
+    StructArray::try_new(Fields::from(fields), columns, merged_validity)
 }
 
 fn merge_with_schema(
@@ -1563,6 +1680,7 @@ impl BufferExt for arrow_buffer::Buffer {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use arrow_array::types::Int32Type;
     use arrow_array::{
         BinaryArray, BinaryViewArray, BooleanArray, FixedSizeBinaryArray, Float32Array, Int32Array,
         LargeBinaryArray, ListArray, NullArray, StringArray, StructArray, new_empty_array,
@@ -2083,6 +2201,493 @@ mod tests {
         assert_eq!(merged, left);
     }
 
+    /// A list of `items`, one item per entry.
+    fn one_item_per_entry(large: bool, items: ArrayRef) -> ArrayRef {
+        let item_field = Arc::new(Field::new("item", items.data_type().clone(), true));
+        let lengths = vec![1; items.len()];
+        if large {
+            Arc::new(LargeListArray::new(
+                item_field,
+                OffsetBuffer::<i64>::from_lengths(lengths),
+                items,
+                None,
+            ))
+        } else {
+            Arc::new(ListArray::new(
+                item_field,
+                OffsetBuffer::<i32>::from_lengths(lengths),
+                items,
+                None,
+            ))
+        }
+    }
+
+    /// A batch with the single column `s`, valid per `parent_validity`.
+    fn batch_of_parent(parent: StructArray) -> RecordBatch {
+        RecordBatch::try_new(
+            Arc::new(Schema::new(vec![Field::new(
+                "s",
+                parent.data_type().clone(),
+                true,
+            )])),
+            vec![Arc::new(parent)],
+        )
+        .unwrap()
+    }
+
+    /// `{s: struct<l: list<struct<{child}: int32>>>}`, one row per value, each
+    /// list holding one item, and `s` valid per `parent_validity`.
+    fn list_struct_under_parent(
+        large: bool,
+        child: &str,
+        parent_validity: &[bool],
+        values: &[i32],
+    ) -> RecordBatch {
+        let items = Arc::new(StructArray::new(
+            vec![Field::new(child, DataType::Int32, true)].into(),
+            vec![Arc::new(Int32Array::from(values.to_vec()))],
+            None,
+        ));
+        let list = one_item_per_entry(large, items);
+        batch_of_parent(StructArray::new(
+            vec![Field::new("l", list.data_type().clone(), true)].into(),
+            vec![list],
+            Some(parent_validity.to_vec().into()),
+        ))
+    }
+
+    /// The child `name` of the single item in row `row` of the merged `s.l`.
+    fn merged_item_child(merged: &RecordBatch, large: bool, row: usize, name: &str) -> ArrayRef {
+        let list = merged.column(0).as_struct().column(0);
+        let item = if large {
+            list.as_list::<i64>().value(row)
+        } else {
+            list.as_list::<i32>().value(row)
+        };
+        item.as_struct().column_by_name(name).unwrap().clone()
+    }
+
+    #[test]
+    fn test_merge_list_struct_identical_schema_hides_a_null_parent_row() {
+        for large in [false, true] {
+            let left = list_struct_under_parent(large, "x", &[false, true], &[11, 12]);
+            let right = list_struct_under_parent(large, "x", &[true, true], &[21, 22]);
+            let merged = left.merge(&right).unwrap();
+            let parent = merged.column(0).as_struct();
+            assert!(parent.is_valid(0), "large={large}");
+            assert!(
+                parent.column(0).is_null(0),
+                "large={large}: the list under the null left parent became visible"
+            );
+            assert!(parent.column(0).is_valid(1), "large={large}");
+        }
+    }
+
+    #[test]
+    fn test_merge_list_struct_hides_the_items_of_a_null_parent_row() {
+        for large in [false, true] {
+            // Null parent on the left: row 0 keeps the right item, not x = 11.
+            let left = list_struct_under_parent(large, "x", &[false, true], &[11, 12]);
+            let right = list_struct_under_parent(large, "y", &[true, true], &[21, 22]);
+            let merged = left.merge(&right).unwrap();
+            assert!(merged.column(0).as_struct().column(0).is_valid(0));
+            assert!(
+                merged_item_child(&merged, large, 0, "x").is_null(0),
+                "large={large}: x under the null left parent became visible"
+            );
+            let y = merged_item_child(&merged, large, 0, "y");
+            assert_eq!(y.as_primitive::<Int32Type>().value(0), 21, "large={large}");
+
+            // Null parent on the right: row 0 keeps x = 11, not y = 21.
+            let left = list_struct_under_parent(large, "x", &[true, true], &[11, 12]);
+            let right = list_struct_under_parent(large, "y", &[false, true], &[21, 22]);
+            let merged = left.merge(&right).unwrap();
+            let x = merged_item_child(&merged, large, 0, "x");
+            assert_eq!(x.as_primitive::<Int32Type>().value(0), 11, "large={large}");
+            assert!(
+                merged_item_child(&merged, large, 0, "y").is_null(0),
+                "large={large}: y under the null right parent became visible"
+            );
+
+            // Row 1 is valid on both sides and keeps both items.
+            let x = merged_item_child(&merged, large, 1, "x");
+            let y = merged_item_child(&merged, large, 1, "y");
+            assert_eq!(x.as_primitive::<Int32Type>().value(0), 12, "large={large}");
+            assert_eq!(y.as_primitive::<Int32Type>().value(0), 22, "large={large}");
+        }
+    }
+
+    #[test]
+    fn test_merge_list_struct_follows_a_sliced_parent() {
+        for large in [false, true] {
+            // After slicing, row 0 is the null parent row and row 1 is valid.
+            let left = list_struct_under_parent(large, "x", &[true, false, true], &[10, 11, 12]);
+            let left = left.slice(1, 2);
+
+            let same = list_struct_under_parent(large, "x", &[true, true, true], &[20, 21, 22]);
+            let merged = left.merge(&same.slice(1, 2)).unwrap();
+            let list = merged.column(0).as_struct().column(0);
+            assert!(list.is_null(0), "large={large}");
+            assert!(list.is_valid(1), "large={large}");
+
+            let other = list_struct_under_parent(large, "y", &[true, true, true], &[20, 21, 22]);
+            let merged = left.merge(&other.slice(1, 2)).unwrap();
+            assert!(
+                merged_item_child(&merged, large, 0, "x").is_null(0),
+                "large={large}"
+            );
+            let x = merged_item_child(&merged, large, 1, "x");
+            assert_eq!(x.as_primitive::<Int32Type>().value(0), 12, "large={large}");
+        }
+    }
+
+    /// A non-nullable `l` or item child cannot be nulled under a parent row that
+    /// only the other side has, so the merge fails there rather than show the
+    /// hidden value. Where both sides agree on the parent, nothing is revealed
+    /// and the same fields merge.
+    #[test]
+    fn test_merge_list_struct_with_non_nullable_fields_under_a_null_parent() {
+        #[derive(Clone, Copy)]
+        struct Shape {
+            child: &'static str,
+            l_nullable: bool,
+            item_nullable: bool,
+            child_nullable: bool,
+            null_first_entry: bool,
+            null_first_item: bool,
+        }
+        let shape = |child| Shape {
+            child,
+            l_nullable: true,
+            item_nullable: true,
+            child_nullable: true,
+            null_first_entry: false,
+            null_first_item: false,
+        };
+        let batch = |shape: Shape, parent_validity: [bool; 2]| {
+            let items = Arc::new(StructArray::new(
+                vec![Field::new(
+                    shape.child,
+                    DataType::Int32,
+                    shape.child_nullable,
+                )]
+                .into(),
+                vec![Arc::new(Int32Array::from(vec![1, 2]))],
+                shape.null_first_item.then(|| vec![false, true].into()),
+            ));
+            let list: ArrayRef = Arc::new(ListArray::new(
+                Arc::new(Field::new(
+                    "item",
+                    items.data_type().clone(),
+                    shape.item_nullable,
+                )),
+                OffsetBuffer::<i32>::from_lengths([1, 1]),
+                items,
+                shape.null_first_entry.then(|| vec![false, true].into()),
+            ));
+            batch_of_parent(StructArray::new(
+                vec![Field::new("l", list.data_type().clone(), shape.l_nullable)].into(),
+                vec![list],
+                Some(parent_validity.to_vec().into()),
+            ))
+        };
+        let null_first = [false, true];
+        let all_valid = [true, true];
+        let cases = [
+            // Non-nullable `l`, identical item types.
+            (
+                Shape {
+                    l_nullable: false,
+                    ..shape("x")
+                },
+                Shape {
+                    l_nullable: false,
+                    ..shape("x")
+                },
+                Some("Cannot merge non-nullable field 'l'"),
+            ),
+            // Non-nullable `l` on the left, a null entry on the right: neither
+            // side has an entry at the merged row.
+            (
+                Shape {
+                    l_nullable: false,
+                    ..shape("x")
+                },
+                Shape {
+                    null_first_entry: true,
+                    ..shape("y")
+                },
+                Some("non-nullable StructArray field \"l\""),
+            ),
+            // A non-nullable child of the item struct.
+            (
+                Shape {
+                    child_nullable: false,
+                    ..shape("x")
+                },
+                shape("y"),
+                Some("Cannot merge non-nullable field 'x'"),
+            ),
+            // A non-nullable item can be hidden where the right item is null.
+            (
+                Shape {
+                    item_nullable: false,
+                    ..shape("x")
+                },
+                Shape {
+                    null_first_item: true,
+                    ..shape("y")
+                },
+                None,
+            ),
+        ];
+        for (case, (left, right, rejected)) in cases.into_iter().enumerate() {
+            let merged = batch(left, null_first).merge(&batch(right, all_valid));
+            match rejected {
+                Some(expected) => {
+                    let message = merged.unwrap_err().to_string();
+                    assert!(message.contains(expected), "case {case}: {message}");
+                }
+                None => assert!(merged.is_ok(), "case {case}: {merged:?}"),
+            }
+            let agreed = batch(left, null_first).merge(&batch(right, null_first));
+            assert!(
+                agreed.is_ok(),
+                "case {case} with agreeing parents: {agreed:?}"
+            );
+        }
+    }
+
+    /// The fragment reader merges a data batch with an all-null placeholder for
+    /// a nested child the file lacks. Only the placeholder's top-level field is
+    /// nullable, so a non-nullable field below it must still merge, in either
+    /// order, keeping the data and filling the new child with nulls.
+    #[test]
+    fn test_merge_with_a_placeholder_under_a_non_nullable_field() {
+        let inner =
+            |child: &str| -> Fields { vec![Field::new(child, DataType::Int32, true)].into() };
+        for wrap in ["struct", "list", "large_list"] {
+            let wrapped = |fields: Fields| match wrap {
+                "struct" => DataType::Struct(fields),
+                "list" => {
+                    DataType::List(Arc::new(Field::new("item", DataType::Struct(fields), true)))
+                }
+                _ => DataType::LargeList(Arc::new(Field::new(
+                    "item",
+                    DataType::Struct(fields),
+                    true,
+                ))),
+            };
+            let outer = |child: &str| {
+                DataType::Struct(vec![Field::new("inner", wrapped(inner(child)), false)].into())
+            };
+            let items: ArrayRef = Arc::new(StructArray::new(
+                inner("a"),
+                vec![Arc::new(Int32Array::from(vec![1, 2]))],
+                None,
+            ));
+            let data_inner = match wrap {
+                "struct" => items,
+                "list" => one_item_per_entry(false, items),
+                _ => one_item_per_entry(true, items),
+            };
+            let data = batch_of_parent(StructArray::new(
+                vec![Field::new("inner", data_inner.data_type().clone(), false)].into(),
+                vec![data_inner],
+                None,
+            ));
+            let placeholder = batch_of_parent(new_null_array(&outer("b"), 2).as_struct().clone());
+
+            for (left, right) in [(&data, &placeholder), (&placeholder, &data)] {
+                let merged = left.merge(right).unwrap();
+                let inner = merged
+                    .column(0)
+                    .as_struct()
+                    .column_by_name("inner")
+                    .unwrap();
+                let items = match wrap {
+                    "struct" => inner.clone(),
+                    "list" => inner.as_list::<i32>().values().clone(),
+                    _ => inner.as_list::<i64>().values().clone(),
+                };
+                let items = items.as_struct();
+                let a = items.column_by_name("a").unwrap();
+                assert_eq!(a.as_primitive::<Int32Type>().values(), &[1, 2], "{wrap}");
+                assert_eq!(a.null_count(), 0, "{wrap}");
+                assert_eq!(items.column_by_name("b").unwrap().null_count(), 2, "{wrap}");
+            }
+        }
+    }
+
+    /// The null parent row's values stay hidden below a struct nested in the
+    /// list item, and below a plain struct field.
+    #[test]
+    fn test_merge_hides_nested_structs_of_a_null_parent_row() {
+        let nested = |child: &str, values: Vec<i32>| {
+            let leaf = StructArray::new(
+                vec![Field::new(child, DataType::Int32, true)].into(),
+                vec![Arc::new(Int32Array::from(values))],
+                None,
+            );
+            StructArray::new(
+                vec![Field::new("payload", leaf.data_type().clone(), true)].into(),
+                vec![Arc::new(leaf)],
+                None,
+            )
+        };
+        let x_of = |payload: &dyn Array, row: usize| {
+            let x = payload.as_struct().column_by_name("x").unwrap().clone();
+            x.is_null(row)
+        };
+
+        for large in [false, true] {
+            let in_list = |child: &str, parent: [bool; 2]| {
+                let list = one_item_per_entry(large, Arc::new(nested(child, vec![11, 12])));
+                batch_of_parent(StructArray::new(
+                    vec![Field::new("l", list.data_type().clone(), true)].into(),
+                    vec![list],
+                    Some(parent.to_vec().into()),
+                ))
+            };
+            let merged = in_list("x", [false, true])
+                .merge(&in_list("y", [true, true]))
+                .unwrap();
+            let list = merged.column(0).as_struct().column(0);
+            let item = if large {
+                list.as_list::<i64>().value(0)
+            } else {
+                list.as_list::<i32>().value(0)
+            };
+            let payload = item.as_struct().column_by_name("payload").unwrap();
+            assert!(x_of(payload.as_ref(), 0), "large={large}");
+        }
+
+        let in_struct = |child: &str, parent: [bool; 2]| {
+            let inner = nested(child, vec![11, 12]);
+            batch_of_parent(StructArray::new(
+                vec![Field::new("c", inner.data_type().clone(), true)].into(),
+                vec![Arc::new(inner)],
+                Some(parent.to_vec().into()),
+            ))
+        };
+        let merged = in_struct("x", [false, true])
+            .merge(&in_struct("y", [true, true]))
+            .unwrap();
+        let c = merged.column(0).as_struct().column(0);
+        let payload = c.as_struct().column_by_name("payload").unwrap();
+        assert!(x_of(payload.as_ref(), 0));
+        assert!(!x_of(payload.as_ref(), 1));
+    }
+
+    /// A batch whose parent rows are all null merges with an all-null
+    /// placeholder whose item struct holds more fields.
+    #[test]
+    fn test_merge_list_struct_under_null_parents_with_a_placeholder() {
+        for large in [false, true] {
+            let a = Field::new("a", DataType::Int32, true);
+            let inner = StructArray::new(
+                vec![a.clone()].into(),
+                vec![Arc::new(Int32Array::from(vec![1, 2]))],
+                None,
+            );
+            let items = Arc::new(StructArray::new(
+                vec![Field::new("x", inner.data_type().clone(), true)].into(),
+                vec![Arc::new(inner)],
+                None,
+            ));
+            let list = one_item_per_entry(large, items);
+            let left = batch_of_parent(StructArray::new(
+                vec![Field::new("l", list.data_type().clone(), true)].into(),
+                vec![list],
+                Some(vec![false, false].into()),
+            ));
+
+            let wider_x =
+                DataType::Struct(vec![a.clone(), Field::new("b", DataType::Int32, true)].into());
+            let wider_items = new_null_array(
+                &DataType::Struct(vec![Field::new("x", wider_x, true)].into()),
+                2,
+            );
+            let wider_list = one_item_per_entry(large, wider_items);
+            let placeholder = new_null_array(
+                &DataType::Struct(
+                    vec![Field::new("l", wider_list.data_type().clone(), true)].into(),
+                ),
+                2,
+            );
+            let right = batch_of_parent(placeholder.as_struct().clone());
+
+            let merged = left.merge(&right).unwrap();
+            assert_eq!(merged.column(0).null_count(), 2, "large={large}");
+        }
+    }
+
+    /// A side whose list entries are all hidden by null parents merges like a
+    /// placeholder, so the other side's lists survive even with other offsets.
+    #[test]
+    fn test_merge_list_struct_hidden_side_keeps_the_other_offsets() {
+        for large in [false, true] {
+            let list_of = |child: &str, lengths: Vec<usize>, values: Vec<i32>| -> ArrayRef {
+                let items: ArrayRef = Arc::new(StructArray::new(
+                    vec![Field::new(child, DataType::Int32, true)].into(),
+                    vec![Arc::new(Int32Array::from(values))],
+                    None,
+                ));
+                let field = Arc::new(Field::new("item", items.data_type().clone(), true));
+                if large {
+                    Arc::new(LargeListArray::new(
+                        field,
+                        OffsetBuffer::<i64>::from_lengths(lengths),
+                        items,
+                        None,
+                    ))
+                } else {
+                    Arc::new(ListArray::new(
+                        field,
+                        OffsetBuffer::<i32>::from_lengths(lengths),
+                        items,
+                        None,
+                    ))
+                }
+            };
+            let parent = |list: ArrayRef, validity: Vec<bool>| {
+                batch_of_parent(StructArray::new(
+                    vec![Field::new("l", list.data_type().clone(), true)].into(),
+                    vec![list],
+                    Some(validity.into()),
+                ))
+            };
+            let left = parent(list_of("x", vec![1, 1], vec![1, 2]), vec![false, false]);
+            let right = parent(list_of("y", vec![2, 0], vec![7, 8]), vec![true, true]);
+
+            let merged = left.merge(&right).unwrap();
+            let list = merged.column(0).as_struct().column(0);
+            let (first, second) = if large {
+                let list = list.as_list::<i64>();
+                (list.value(0), list.value(1))
+            } else {
+                let list = list.as_list::<i32>();
+                (list.value(0), list.value(1))
+            };
+            let first = first.as_struct();
+            assert_eq!(
+                first
+                    .column_by_name("y")
+                    .unwrap()
+                    .as_primitive::<Int32Type>()
+                    .values(),
+                &[7, 8],
+                "large={large}"
+            );
+            assert_eq!(
+                first.column_by_name("x").unwrap().null_count(),
+                2,
+                "large={large}"
+            );
+            assert_eq!(second.len(), 0, "large={large}");
+        }
+    }
+
     #[test]
     fn test_byte_width_opt() {
         assert_eq!(DataType::Int32.byte_width_opt(), Some(4));
@@ -2315,7 +2920,7 @@ mod tests {
         );
 
         // Merge the two structs
-        let merged = merge(&left_struct, &right_struct);
+        let merged = merge(&left_struct, &right_struct).unwrap();
 
         // Expected:
         // Row 1: both non-null -> {width: 300, height: 500}
@@ -2355,7 +2960,7 @@ mod tests {
             Some(vec![false, false].into()),
         );
 
-        let merged = merge(&all_null_left, &all_null_right);
+        let merged = merge(&all_null_left, &all_null_right).unwrap();
         assert_eq!(merged.null_count(), 2);
 
         // An all-null side is the identity of the merge, so the other side decides each row.
@@ -2364,7 +2969,7 @@ mod tests {
             vec![Arc::new(Int32Array::from(vec![Some(1), None])) as ArrayRef],
             Some(vec![true, false].into()),
         );
-        let merged = merge(&partial_left, &all_null_right);
+        let merged = merge(&partial_left, &all_null_right).unwrap();
         assert!(!merged.is_null(0));
         assert!(merged.is_null(1));
 
@@ -2374,7 +2979,7 @@ mod tests {
             vec![Arc::new(Int32Array::from(vec![1, 2])) as ArrayRef],
             None,
         );
-        let merged = merge(&all_valid_left, &all_null_right);
+        let merged = merge(&all_valid_left, &all_null_right).unwrap();
         assert_eq!(merged.null_count(), 0);
 
         // An explicit all-valid buffer has the same semantics as a missing buffer.
@@ -2401,7 +3006,7 @@ mod tests {
         );
 
         // Previously panicked: "Arrays of type Null cannot contain a null bitmask"
-        let merged = merge(&left_struct, &right_struct);
+        let merged = merge(&left_struct, &right_struct).unwrap();
         assert_eq!(merged.len(), 2);
         let b_col = merged.column_by_name("b").unwrap();
         // DataType::Null implies all-null by definition; no null bitmap is stored.
diff --git a/python/vendor/lance-arrow/src/stream.rs b/python/vendor/lance-arrow/src/stream.rs
index c5e55f093..5aee834fd 100644
--- a/python/vendor/lance-arrow/src/stream.rs
+++ b/python/vendor/lance-arrow/src/stream.rs
@@ -8,16 +8,21 @@ use arrow_array::RecordBatch;
 use arrow_schema::{ArrowError, SchemaRef};
 use futures::stream::{self, Stream, StreamExt};
 use std::pin::Pin;
+use std::vec::IntoIter;
 
 use crate::deepcopy::deep_copy_batch_sliced;
 
 /// Rechunks a stream of [`RecordBatch`] so that each output batch has
-/// approximately `target_bytes` of array data.
+/// approximately `max_bytes` of array data.
 ///
 /// Small input batches are accumulated (by concatenation) until at least
 /// `min_bytes` of data has been collected. If the resulting batch exceeds
 /// `max_bytes`, it is sliced into roughly equal pieces of ~`max_bytes`
 /// (assuming uniform row sizes).
+///
+/// Slices share the input's buffers, so their array memory sizes may still
+/// report the full parent allocation. Once split, all slices are delivered
+/// directly, including a final slice smaller than `min_bytes`.
 pub fn rechunk_stream_by_size<S, E>(
     input: S,
     input_schema: SchemaRef,
@@ -74,6 +79,7 @@ where
         RechunkState {
             input: Box::pin(input),
             accumulated: Vec::new(),
+            slices: Vec::new().into_iter(),
             acc_bytes: 0,
             done: false,
             input_schema,
@@ -82,6 +88,12 @@ where
             deep_copy,
         },
         |mut state| async move {
+            // These slices are already sized. Measuring their shared buffers
+            // again would repeatedly split the tail using the parent size.
+            if let Some(batch) = state.slices.next() {
+                return Ok(Some((batch, state)));
+            }
+
             if state.done && state.accumulated.is_empty() {
                 return Ok(None);
             }
@@ -106,17 +118,6 @@ where
                 return Ok(None);
             }
 
-            // Fast path: if the first accumulated batch already meets the
-            // byte threshold, deliver it directly instead of concatenating
-            // everything together (which would just get sliced back apart).
-            if state.accumulated.len() > 1
-                && state.accumulated[0].get_array_memory_size() >= state.min_bytes
-            {
-                let b = state.accumulated.remove(0);
-                state.acc_bytes -= b.get_array_memory_size();
-                return Ok(Some((b, state)));
-            }
-
             let batch = if state.accumulated.len() == 1 {
                 state.accumulated.pop().unwrap()
             } else {
@@ -132,19 +133,9 @@ where
             let mut slices =
                 slice_batch(batch, state.max_bytes, state.deep_copy).map_err(E::from)?;
 
-            if slices.len() == 1 {
-                Ok(Some((slices.pop().unwrap(), state)))
-            } else {
-                let first = slices.remove(0);
-
-                // Stash leftover slices for subsequent iterations.
-                for a in &slices {
-                    state.acc_bytes += a.get_array_memory_size();
-                }
-                state.accumulated = slices;
-
-                Ok(Some((first, state)))
-            }
+            let first = slices.remove(0);
+            state.slices = slices.into_iter();
+            Ok(Some((first, state)))
         },
     )
 }
@@ -206,12 +197,13 @@ fn slice_batch(
     Ok(result)
 }
 
-/// Internal state for [`rechunk_stream`].
+/// Internal state for [`rechunk_stream_by_size`].
 ///
 /// Kept as a named struct so the `try_unfold` closure stays readable.
 struct RechunkState<S> {
     input: Pin<Box<S>>,
     accumulated: Vec<RecordBatch>,
+    slices: IntoIter<RecordBatch>,
     acc_bytes: usize,
     done: bool,
     input_schema: SchemaRef,
@@ -339,9 +331,9 @@ mod tests {
 
     #[test]
     fn test_sliced_leftovers_are_not_recombined() {
-        // Key test for the fast-path optimisation. When a large batch is
-        // sliced, leftover slices should be delivered one-at-a-time without
-        // being concatenated back together.  We verify this by checking that
+        // When a large batch is sliced, leftover slices should be delivered
+        // one at a time without being split again or concatenated back
+        // together. We verify zero-copy behavior by checking that
         // every output buffer pointer falls inside the original batch's
         // allocation (i.e. they are all zero-copy slices, not fresh copies).
         let batch = make_batch(1000);
@@ -354,7 +346,11 @@ mod tests {
         let result = collect_rechunked(vec![batch], bytes / 8, bytes / 4);
 
         assert_eq!(total_rows(&result), 1000);
-        assert!(result.len() >= 4);
+        assert_eq!(
+            result.iter().map(RecordBatch::num_rows).collect::<Vec<_>>(),
+            vec![250, 250, 250, 250],
+            "leftover slices must not be split again using the parent buffer size"
+        );
 
         for (i, b) in result.iter().enumerate() {
             let ptr = b.column(0).to_data().buffers()[0].as_ptr() as usize;
@@ -381,6 +377,7 @@ mod tests {
         // After a large batch is fully drained, subsequent small batches
         // should be accumulated normally.
         let large = make_batch(1000);
+        let large_bytes = large.get_array_memory_size();
         let small_bytes = make_batch(10).get_array_memory_size();
         let batches = vec![
             large,
@@ -390,12 +387,12 @@ mod tests {
             make_batch(10),
             make_batch(10),
         ];
-        let result = collect_rechunked(batches, small_bytes * 3, small_bytes * 100);
+        let result = collect_rechunked(batches, small_bytes * 3, large_bytes / 4);
         assert_eq!(total_rows(&result), 1050);
-        // The large batch should appear (possibly sliced) followed by
-        // concatenated small batches, so we should have fewer output batches
-        // than the 6 inputs.
-        assert!(result.len() < 6);
+        assert_eq!(
+            result.iter().map(RecordBatch::num_rows).collect::<Vec<_>>(),
+            vec![250, 250, 250, 250, 30, 20]
+        );
     }
 
     #[test]
@@ -441,10 +438,9 @@ mod tests {
         let bytes = batch.get_array_memory_size();
         let result = collect_rechunked(vec![batch], 0, bytes / 4);
         assert_eq!(total_rows(&result), 1000);
-        assert!(
-            result.len() >= 4,
-            "expected at least 4 slices, got {}",
-            result.len()
+        assert_eq!(
+            result.iter().map(RecordBatch::num_rows).collect::<Vec<_>>(),
+            vec![250, 250, 250, 250]
         );
     }
 
@@ -475,6 +471,25 @@ mod tests {
         Arc::new(Schema::new(vec![Field::new("s", DataType::Utf8, false)]))
     }
 
+    #[test]
+    fn test_variable_length_tail_is_not_resliced() {
+        let batch = make_variable_batch(100, 256, usize::MAX, 256);
+        let bytes = batch.get_array_memory_size();
+        let max_bytes = bytes - bytes / 4;
+        let input = stream::iter(vec![Ok::<_, ArrowError>(batch)]);
+        let rechunked = rechunk_stream_by_size(input, variable_schema(), max_bytes, max_bytes);
+        let result: Vec<_> = block_on(rechunked.collect::<Vec<_>>())
+            .into_iter()
+            .map(Result::unwrap)
+            .collect();
+
+        assert_eq!(
+            result.iter().map(RecordBatch::num_rows).collect::<Vec<_>>(),
+            vec![75, 25]
+        );
+        assert_eq!(total_rows(&result), 100);
+    }
+
     fn collect_rechunked_variable(
         batches: Vec<RecordBatch>,
         min_bytes: usize,
diff --git a/rust/lancedb/Cargo.toml b/rust/lancedb/Cargo.toml
index 62029bb92..7f3764b02 100644
--- a/rust/lancedb/Cargo.toml
+++ b/rust/lancedb/Cargo.toml
@@ -46,7 +46,7 @@ lance-index = { workspace = true, features = ["tokenizer-jieba", "tokenizer-lind
 lance-table = { workspace = true }
 lance-linalg = { workspace = true }
 lance-encoding = { workspace = true }
-lance-arrow = { version = "=15.0.0-beta.1", tag = "v15.0.0-beta.1", git = "https://github.com/lance-format/lance.git" }
+lance-arrow = { "version" = "=15.0.0-beta.2", "tag" = "v15.0.0-beta.2", "git" = "https://github.com/lance-format/lance.git" }
 lance-namespace = { workspace = true }
 lance-namespace-impls = { workspace = true }
 metrics = { workspace = true, optional = true }
diff --git a/rust/lancedb/src/blob.rs b/rust/lancedb/src/blob.rs
index 142b2264e..07808d56c 100644
--- a/rust/lancedb/src/blob.rs
+++ b/rust/lancedb/src/blob.rs
@@ -687,6 +687,8 @@ async fn map_blob_take_error(
     let message = err.to_string();
     let missing_row_id = message.contains("must not target deleted rows")
         || message.contains("belongs to non-existent fragment")
+        || (message.contains("Unknown fragment id ")
+            && message.contains("in fragment filter; not part of the current dataset version"))
         || (message.contains("Invalid read params ") && message.contains("addressable rows"))
         || message.contains("Could not resolve all requested row IDs");
 
diff --git a/rust/lancedb/src/table/merge.rs b/rust/lancedb/src/table/merge.rs
index 91a0ed6ea..a066a4d6d 100644
--- a/rust/lancedb/src/table/merge.rs
+++ b/rust/lancedb/src/table/merge.rs
@@ -2137,7 +2137,7 @@ mod lsm_tests {
         }
         fn training_criteria(&self) -> lance_index::scalar::registry::TrainingCriteria {
             use lance_index::scalar::registry::{TrainingCriteria, TrainingOrdering};
-            TrainingCriteria::new(TrainingOrdering::Values).with_row_id()
+            TrainingCriteria::new(TrainingOrdering::Values).with_row_addr()
         }
         fn validate(
             &self,
@@ -2181,24 +2181,8 @@ mod lsm_tests {
             &self,
             ctx: &lance::dataset::mem_wal::index::FlushContext<'_>,
         ) -> lance_core::Result<lance::dataset::mem_wal::index::FlushOutcome> {
-            // BTree now trains on row addresses, while Bitmap still takes row IDs.
-            // These coincide in the flushed generation, which uses physical IDs.
-            assert!(!ctx.generation()?.dataset.manifest().uses_stable_row_ids());
-            let batches = self
-                .0
-                .to_training_batches(ctx.batch_size)?
-                .into_iter()
-                .map(|batch| {
-                    assert_eq!(batch.schema().field(1).name(), lance_core::ROW_ADDR);
-                    let schema = Arc::new(Schema::new(vec![
-                        batch.schema().field(0).clone(),
-                        Field::new(lance_core::ROW_ID, DataType::UInt64, false),
-                    ]));
-                    RecordBatch::try_new(schema, batch.columns().to_vec())
-                })
-                .collect::<std::result::Result<Vec<_>, _>>()?;
             Ok(lance::dataset::mem_wal::index::FlushOutcome::from_batches(
-                batches,
+                self.0.to_training_batches(ctx.batch_size)?,
             ))
         }
     }