4cdaba778d
This pull request introduces support for global secondary indexes based on static columns. Local secondary indexes based on secondary columns are not planned to be supported and are explicitly forbidden. Because there is only one static row per partition and local indexes require full partition key when querying, such indexes wouldn't be very useful and would only waste resources. The index table for secondary indexes on static columns, unlike other secondary indexes, do not contain clustering keys from the base table. A static column's value determines a set of full partitions, so the clustering keys would only be unnecessary. The already existing logic for querying using secondary indexes works after introducing minimal notifications. The view update generation path now works on a common representation of static and clustering rows, but the new representation allowed to keep most of the logic intact. New cql-pytests are added. All but one of the existing tests for secondary indexes on static columns - ported from Cassandra - now work and have their `xfail` marks lifted; the remaining test requires support for collection indexing, so it will start working only after #2962 is fixed. Materialized view with static rows as a key are __not__ implemented in this PR. Fixes: #2963 Closes #11166 * github.com:scylladb/scylladb: test_materialized_view: verify that static columns are not allowed test_secondary_index: add (currently failing) test for static index paging test_secondary_index: add more tests for secondary indexes on static columns cassandra_tests: enable existing tests for static columns create_index_statement: lift restriction on secondary indexes on static rows db/view: fetch and process static rows when building indexes gms/feature_service: introduce SECONDARY_INDEXES_ON_STATIC_COLUMNS cluster feature create_index_statement: disallow creation of local indexes with static columns select_statement: prepare paging for indexes on static columns select_statement: do not attempt to fetch clustering columns from secondary index's table secondary_index_manager: don't add clustering key columns to index table of static column index replica/table: adjust the view read-before-write to return static rows when needed db/view: process static rows in view_update_builder::on_results db/view: adjust existing view update generation path to use clustering_or_static_row column_computation: adjust to use clustering_or_static_row db/view: add clustering_or_static_row deletable_row: add column_kind parameter to is_live view_info: adjust view_column to accept column_kind db/view: base_dependent_view_info: split non-pk columns into regular and static
Scylla
What is Scylla?
Scylla is the real-time big data database that is API-compatible with Apache Cassandra and Amazon DynamoDB. Scylla embraces a shared-nothing approach that increases throughput and storage capacity to realize order-of-magnitude performance improvements and reduce hardware costs.
For more information, please see the ScyllaDB web site.
Build Prerequisites
Scylla is fairly fussy about its build environment, requiring very recent versions of the C++20 compiler and of many libraries to build. The document HACKING.md includes detailed information on building and developing Scylla, but to get Scylla building quickly on (almost) any build machine, Scylla offers a frozen toolchain, This is a pre-configured Docker image which includes recent versions of all the required compilers, libraries and build tools. Using the frozen toolchain allows you to avoid changing anything in your build machine to meet Scylla's requirements - you just need to meet the frozen toolchain's prerequisites (mostly, Docker or Podman being available).
Building Scylla
Building Scylla with the frozen toolchain dbuild is as easy as:
$ git submodule update --init --force --recursive
$ ./tools/toolchain/dbuild ./configure.py
$ ./tools/toolchain/dbuild ninja build/release/scylla
For further information, please see:
- Developer documentation for more information on building Scylla.
- Build documentation on how to build Scylla binaries, tests, and packages.
- Docker image build documentation for information on how to build Docker images.
Running Scylla
To start Scylla server, run:
$ ./tools/toolchain/dbuild ./build/release/scylla --workdir tmp --smp 1 --developer-mode 1
This will start a Scylla node with one CPU core allocated to it and data files stored in the tmp directory.
The --developer-mode is needed to disable the various checks Scylla performs at startup to ensure the machine is configured for maximum performance (not relevant on development workstations).
Please note that you need to run Scylla with dbuild if you built it with the frozen toolchain.
For more run options, run:
$ ./tools/toolchain/dbuild ./build/release/scylla --help
Testing
See test.py manual.
Scylla APIs and compatibility
By default, Scylla is compatible with Apache Cassandra and its APIs - CQL and Thrift. There is also support for the API of Amazon DynamoDB™, which needs to be enabled and configured in order to be used. For more information on how to enable the DynamoDB™ API in Scylla, and the current compatibility of this feature as well as Scylla-specific extensions, see Alternator and Getting started with Alternator.
Documentation
Documentation can be found here. Seastar documentation can be found here. User documentation can be found here.
Training
Training material and online courses can be found at Scylla University. The courses are free, self-paced and include hands-on examples. They cover a variety of topics including Scylla data modeling, administration, architecture, basic NoSQL concepts, using drivers for application development, Scylla setup, failover, compactions, multi-datacenters and how Scylla integrates with third-party applications.
Contributing to Scylla
If you want to report a bug or submit a pull request or a patch, please read the contribution guidelines.
If you are a developer working on Scylla, please read the developer guidelines.
Contact
- The users mailing list and Slack channel are for users to discuss configuration, management, and operations of the ScyllaDB open source.
- The developers mailing list is for developers and people interested in following the development of ScyllaDB to discuss technical topics.