cc85c4fb7a
Adds logic into prep_alter_part_table() for INTERVAL ... AUTO to read the history range (vers_get_history_range()) and size the new layout from it. STARTS is aligned to the oldest history row_end (vers_set_starts()) if it was not specified by the user, or if the user specified it later than that; in the latter case WARN_VERS_WRONG_STARTS is printed. The history partitions cover both the newest history row_end and the query time, so DML after the ALTER does not need to create partitions. A PARTITIONS N clause is kept if it gives more partitions. An explicit subpartition list is replaced by as many default subpartitions. If the layout needs more than MAX_PARTITIONS partitions (counting subpartitions), or the INTERVAL is longer than the date range, the ALTER fails with ER_VERS_HIST_PART_FAILED. Month and year intervals are stepped in UTC; a boundary past the maximum TIMESTAMP ends a partial last history partition. In case of fast ALTER TABLE, f.ex. when partitioning already exists, the above logic is ignored unless FORCE clause is specified. When user specifies partition list explicitly the above logic is ignored even with FORCE clause. With FORCE on a table already partitioned by SYSTEM_TIME the work is done on a clone of the partitioning info. The parsed settings are copied into the clone's vers_info with Vers_part_info::copy_settings(), which keeps the clone's now_part and hist_part (the parsed ones are NULL). Before reading the range, the metadata lock is upgraded to MDL_SHARED_NO_WRITE, and then the copy does not run online, so DML cannot add history that would not fit the computed layout until the ALTER ends (Alter_info::vers_history_read). LOCK=NONE and ALGORITHM=INPLACE/NOCOPY/INSTANT are rejected for such ALTER before the upgrade, so they do not wait for concurrent DML; the ALGORITHM error is reported by the new Alter_info::report_algorithm_unsupported(), which mysql_alter_table() uses as well. The range is read under a table lock taken with mysql_lock_tables(), as some engines (Aria) set up their transaction in THR_LOCK callbacks. The scan can be killed. WARN_VERS_STARTS_BEYOND_INTERVAL for ALTER .. AUTO is checked after the alignment, so it is not printed when STARTS was re-aligned to the history. vers_get_history_range() detects if an index can be used for row_end min/max stats and if so it gets it with ha_index_first() and HA_READ_BEFORE_KEY (as it must ignore current data). Otherwise it does a table scan to read the stats. Current rows with the pre-11.5 row_end marker are not taken for history either. In the index they sort below history after 2038, so the minimum is read after them. There is test_mdev-25529 debug keyword to check the both and compare results. WARN_VERS_SLOW_ROW_END is printed if the scan read any row and there is no usable index (a disabled one does not count as missing). Static key_cmp was renamed to key_eq to resolve compilation after key.h was included as key_cmp was already declared there.
MariaDB Server
MariaDB Server is one of the most widely deployed open source relational databases. It is built by a global community of contributors together with the MariaDB Foundation and MariaDB plc, and it powers workloads from small applications to large-scale production systems.
MariaDB began as a fork of MySQL, led by the original MySQL developers, and it maintains a high degree of MySQL compatibility. It has since grown into a database with its own capabilities, including native vector search, multiple pluggable storage engines, synchronous clustering, and analytical features, while remaining a straightforward migration target for existing MySQL deployments.
Key features
- Native vector search. A built-in VECTOR data type with approximate nearest-neighbour indexing (HNSW), available since MariaDB 11.8 with no extension required.
- Pluggable storage engines. InnoDB (default for transactional workloads), Aria, MyRocks, ColumnStore for analytics, Spider for sharding, and S3 for archival, among others.
- Replication and clustering. Asynchronous, semi-synchronous, and parallel replication with global transaction IDs, plus Galera synchronous multi-primary clustering.
- Advanced SQL. Common table expressions and recursive CTEs, window functions, system-versioned (temporal) tables, sequences, and a broad set of JSON functions.
- MySQL and Oracle compatibility. Wire-protocol and syntax compatibility with MySQL, plus an Oracle SQL mode supporting PL/SQL-style stored routines.
- Spatial and full-text search. GIS data types and functions, and built-in full-text indexing.
- Security. Role-based access control, pluggable authentication (ed25519, PAM, GSSAPI, and more), data-at-rest encryption, and TLS for connections.
Documentation
- Project home, community, and getting involved
- Reference manual and release notes
- MariaDB compared to MySQL
Releases
MariaDB Server follows a yearly long-term support (LTS) model alongside quarterly rolling releases. Binary LTS releases are maintained for three years and are recommended for production; rolling releases deliver new features sooner with a shorter support window.
For the current version and full history, see Releases and the MariaDB release calendar.
Installing
Packages and installation instructions for all supported platforms are available at https://mariadb.org/download/.
Building from source
To build MariaDB from source and run the test suite, follow the developer guide
It covers building the code correctly, running the MariaDB testing framework, and choosing the right branch to target for contributions.
Contributing
Contributions are welcome, from code and documentation to bug reports and reviews. See CONTRIBUTING.md to get started, and CODING_STANDARDS.md for code style. Contributors and community members are recognised in CREDITS.
Getting help
- Zulip chat
- Maria Discuss mailing list
- Bug reports
- Security vulnerabilities: see SECURITY.md
Licensing
MariaDB Server is licensed under version 2 of the GNU General Public License (GPLv2), without the "any later version" clause. This is inherited from MySQL. License information is in the COPYING file, and third-party license information is in the THIRDPARTY file.
About MariaDB Foundation
MariaDB is brought to you by the MariaDB Foundation and MariaDB plc. The MariaDB Foundation is the custodian of the MariaDB Server codebase, ensuring it stays open and that anyone can contribute. See CREDITS for details on the Foundation and the people developing MariaDB.
MySQL, the base of MariaDB, is a product and trademark of Oracle Corporation, Inc.