a72dde2ee6
Scylla inherited a 48-character limit on the length of table (and keyspace) names from Cassandra 3. It turns out that Cassandra 4 and 5 unintentionally dropped this limit (see history lesson in CASSANDRA-20425), and now Cassandra accepts longer table names. Some Cassandra users are using such longer names and disappointed that Scylla doesn't allow them. This patch includes tests for this feature. One test tries a 48-character table name - it passes on Scylla and all versions of Cassandra. A second test tries a 100-character table name - this one passes on Cassandra version 4 and above (but not on 3), and fails on Scylla so marked "xfail". A third test tries a 500-character table name. This one fails badly on Cassandra (see CASSANDRA-20389), but passes on Scylla today. This test is important because we need to be sure that it continues to pass on Scylla even after the Scylla is fixed to allow the 100-character test. Refs #4480 - an issue we already have about supporting longer names Note on the test implementation: Ideally, the test for a particular table-name length shouldn't just create the table - it should also make sure we can write table to it and flush it, i.e., that sstables can get written correctly. But in practice, these complications are not needed, because in modern Scylla it is the directory name which contains the table's name, and the individual sstable files do not contain the table's name. Just creating the table already creates the long directory name, so that is the part that needs to be tested. If we created this directory successfully, later creating the short-named sstables inside it can't fail. Signed-off-by: Nadav Har'El <nyh@scylladb.com> Closes scylladb/scylladb#23229
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++23 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 API - CQL. 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 community forum and Slack channel are for users to discuss configuration, management, and operations of ScyllaDB.
- The developers mailing list is for developers and people interested in following the development of ScyllaDB to discuss technical topics.