96dd3121e7
CassIO (the library backing LangChain's `langchain_community.vectorstores.Cassandra` integration) issues the following DDL during schema setup to create a metadata index: ```sql CREATE CUSTOM INDEX IF NOT EXISTS eidx_metadata_s_<table> ON <keyspace>.<table> (ENTRIES(metadata_s)) USING 'org.apache.cassandra.index.sai.StorageAttachedIndex'; ``` ScyllaDB does not support Cassandra's StorageAttachedIndex (SAI) for non-vector columns and previously rejected this statement with: ``` StorageAttachedIndex (SAI) is only supported on vector columns; use a secondary index for non-vector columns ``` This blocks seamless migration of existing LangChain/CassIO applications from Cassandra to ScyllaDB — applications fail during initialization before any application-level workaround can run, even when metadata filtering is not used (`metadata_indexing="none"`). CassIO is no longer actively maintained but remains the only official LangChain integration path for Apache Cassandra over CQL, meaning existing applications will continue using this setup pattern. Instead of rejecting the CassIO metadata-map SAI DDL, detect the pattern and rewrite it to a standard ScyllaDB secondary index on collection entries: - **Detection**: SAI class name + single `ENTRIES` target on a non-frozen `map` column - **Rewrite**: Clear the custom class so the index is created through the standard secondary index path (which already fully supports indexing map entries) - **Warning**: Emit a CQL warning informing the user that SAI is not supported by ScyllaDB, a regular secondary index was created instead, and metadata filtering behavior may differ from Cassandra SAI The rewrite is placed early in `validate_while_executing()`, before the rf-rack-validity check, so the standard secondary index code path handles all subsequent validation naturally — no code duplication. After this change, the CassIO schema setup succeeds on ScyllaDB: - `CREATE CUSTOM INDEX ... USING 'sai'` on `ENTRIES(metadata_s)` creates a real secondary index - The index is functional and can accelerate metadata filtering queries - A CQL warning makes the rewrite transparent to operators - SAI on non-vector, non-map-entries columns is still rejected as before - Vector SAI indexes continue to be rewritten to `vector_index` as before - `test_sai_entries_on_map_creates_regular_index` — verifies the index is created and the warning is emitted (fully-qualified SAI class name) - `test_sai_entries_on_map_short_name` — same with the `'sai'` short alias - `test_sai_on_regular_column_rejected` — confirms SAI on regular scalar columns is still rejected All 148 tests in `test_vector_index.py` and `test_secondary_index.py` pass with no regressions (125 passed, 22 xfailed, 1 skipped). Fixes: SCYLLADB-2113 Backport: 2026.2 as this is the version where the support for SAI class needed by LangChain was added. Closes scylladb/scylladb#29981 * github.com:scylladb/scylladb: cql: rewrite CassIO SAI metadata index to regular secondary index db/config: add enable_cassio_compatibility flag
ScyllaDB Documentation
This repository contains the source files for ScyllaDB documentation.
- The
devfolder contains developer-oriented documentation related to the ScyllaDB code base. It is not published and is only available via GitHub. - All other folders and files contain user-oriented documentation related to ScyllaDB and are sources for docs.scylladb.com/manual.
To report a documentation bug or suggest an improvement, open an issue in GitHub issues for this project.
To contribute to the documentation, open a GitHub pull request.
Key Guidelines for Contributors
- The user documentation is written in reStructuredText (RST) - a plaintext markup language similar to Markdown. If you're not familiar with RST, see ScyllaDB RST Examples.
- The developer documentation is written in Markdown. See Basic Markdown Syntax for reference.
- Follow the ScyllaDB Style Guide.
To prevent the build from failing:
-
If you add a new file, ensure it's added to an appropriate toctree, for example:
.. toctree:: :maxdepth: 2 :hidden: Page X </folder1/article1> Page Y </folder1/article2> Your New Page </folder1/your-new-article> -
Make sure the link syntax is correct. See the guidelines on creating links
-
Make sure the section headings are correct. See the guidelines on creating headings Note that the markup must be at least as long as the text in the heading. For example:
---------------------- Prerequisites ----------------------
Building User Documentation
Prerequisites
- Python
- poetry
- make
See the ScyllaDB Sphinx Theme prerequisites to check which versions of the above are currently required.
Mac OS X
You must have a working Homebrew in order to install the needed tools.
You also need the standard utility make.
Check if you have these two items with the following commands:
brew help
make -h
Linux Distributions
Building the user docs should work out of the box on most Linux distributions.
Windows
Use "Bash on Ubuntu on Windows" for the same tools and capabilities as on Linux distributions.
Building the Docs
- Run
make previewin thedocs/directory to build the documentation. - Preview the built documentation locally at http://127.0.0.1:5500/.
Cleanup
You can clean up all the build products and auto-installed Python stuff with:
make pristine
Information for Contributors
If you are interested in contributing to Scylla docs, please read the Scylla open source page at http://www.scylladb.com/opensource/ and complete a Scylla contributor agreement if needed. We can only accept documentation pull requests if we have a contributor agreement on file for you.
Third-party Documentation
-
Do any copying as a separate commit. Always commit an unmodified version first and then do any editing in a separate commit.
-
We already have a copy of the Apache license in our tree, so you do not need to commit a copy of the license.
-
Include the copyright header from the source file in the edited version. If you are copying an Apache Cassandra document with no copyright header, use:
This document includes material from Apache Cassandra.
Apache Cassandra is Copyright 2009-2014 The Apache Software Foundation.