Simplify experimental materialized views to one output-only storage
layout and one full-rebuild refresh implementation.
## Current layout
Local materialized views currently maintain incremental-refresh state
alongside the materialized values:
- an internal `__source_row_id` column for source provenance;
- `mv.definition` plus `mv.incarnation`;
- source version/timestamp, view version, and last-refresh watermarks;
- optional `mv.staging` state for table-function sources; and
- stable-row-ID requirements on the source table.
Refresh classifies source changes, appends or evicts rows when possible,
and falls back to a rebuild for unsupported deltas. Remote
create/refresh also use separate REST mutation paths.
## New layout
An MV is an ordinary Lance backing table containing only:
- the defining query's output columns;
- its current data fragments; and
- `mv.definition`, encoded as a versioned SQL envelope such as
`{"kind":"query","format":1,"query":"SELECT ..."}`.
There is no provenance column, incarnation, source/view watermark,
staging metadata, or stable-row-ID requirement. Local refresh may still
pin a source version for reproducibility, but it always recomputes the
complete result.
Full refresh streams the new result into uncommitted fragments and then
publishes a single transaction that removes every old fragment and
installs the new set. A shared conflict token prevents concurrent
replacements from both committing. This fragment-replacement primitive
is also used by Sophon's SQL worker.
## New remote create workflow
```text
Connection::create_materialized_view(...)
-> builder renders the defining SELECT
-> remote Database receives a CreateMaterializedViewRequest
-> submit CREATE MATERIALIZED VIEW ... AS ... through Flight SQL
-> retain the SQL Query handle while the Job is running
-> consume the durable SQL-job result
-> open the created table and read mv.definition
-> return MaterializedView
```
Remote refresh similarly submits `REFRESH MATERIALIZED VIEW` through
Flight SQL. Cancelling either wrapper forwards cancellation to the
retained SQL query before aborting the local task, so the server
operation is not silently left running.
## API changes
- remove incremental/no-op modes and the `full` switch;
- remove distributed grouped/partitioned refresh APIs and native
vector-source MV APIs;
- keep full-refresh results across Rust, Python, and TypeScript;
- preserve list/describe/drop as object-management operations while
routing create/refresh mutations through SQL.
The storage contract is experimental and has no compatibility shim;
views using the removed layout must be recreated.
LanceDB Documentation
LanceDB docs are available at docs.lancedb.com.
The SDK docs are built and deployed automatically by Github Actions
whenever a commit is pushed to the main branch. So it is possible for the docs to show
unreleased features.
Building the docs
Setup
- Install LanceDB Python. See setup in Python contributing guide.
Run
make developto install the Python package. - Install documentation dependencies. From LanceDB repo root:
pip install -r docs/requirements.txt
Preview the docs
cd docs
mkdocs serve
If you want to just generate the HTML files:
PYTHONPATH=. mkdocs build -f docs/mkdocs.yml
If successful, you should see a docs/site directory that you can verify locally.
Adding examples
To make sure examples are correct, we put examples in test files so they can be run as part of our test suites.
You can see the tests are at:
- Python:
python/python/tests/docs - Typescript:
nodejs/examples/
Checking python examples
cd python
pytest -vv python/tests/docs
Checking typescript examples
The examples depend on @lancedb/lancedb at file:../dist, so the package must be
built before running the tests. This uses pnpm; see the
Typescript contributing guide for the toolchain setup.
pushd nodejs
pnpm install
pnpm build
popd
Then you can run the examples by going to the nodejs/examples directory, which is a
separate pnpm package with its own lockfile:
pushd nodejs/examples
pnpm install
pnpm test
popd
API documentation
Python
The Python API documentation is organized based on the file docs/src/python/python.md.
We manually add entries there so we can control the organization of the reference page.
However, this means any new types must be manually added to the file. No additional
steps are needed to generate the API documentation.
Typescript
The typescript API documentation is generated from the typescript source code using typedoc.
When new APIs are added, you must manually re-run the typedoc command to update the API documentation. The new files should be checked into the repository.
pushd nodejs
# `pnpm docs` would invoke pnpm's built-in `docs` command, not the script.
pnpm run docs
popd