Compression is stored in unireg_check as Field::TMYSQL_COMPRESSED, but has_default_function() treated any unireg_check other than Field::NONE as a default function. A COMPRESSED NOT NULL column without an explicit DEFAULT therefore never got NO_DEFAULT_VALUE_FLAG, the FRM was written without FIELDFLAG_NO_DEFAULT, and the column silently became optional while SHOW CREATE TABLE displayed a phantom DEFAULT ''. Exclude TMYSQL_COMPRESSED in has_default_function() and use that method in Column_definition::check() as well, so that both places which set NO_DEFAULT_VALUE_FLAG stay in sync. Tables created before the fix keep the wrong implicit DEFAULT '' in their FRM and are not repaired automatically, the affected columns need an explicit ALTER TABLE ... MODIFY. Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Code status:
MariaDB: The innovative open source database
MariaDB was designed as a drop-in replacement of MySQL(R) with more features, new storage engines, fewer bugs, and better performance.
MariaDB is brought to you by the MariaDB Foundation and the MariaDB Corporation. Please read the CREDITS file for details about the MariaDB Foundation, and who is developing MariaDB.
MariaDB is developed by many of the original developers of MySQL who now work for the MariaDB Corporation, the MariaDB Foundation and by many people in the community.
MySQL, which is the base of MariaDB, is a product and trademark of Oracle Corporation, Inc. For a list of developers and other contributors, see the Credits appendix. You can also run 'SHOW authors' to get a list of active contributors.
A description of the MariaDB project and a manual can be found at:
https://mariadb.com/docs/release-notes
Getting the code, building it and testing it
Refer to the following guide: https://mariadb.org/get-involved/getting-started-for-developers/get-code-build-test/ which outlines how to build the source code correctly and run the MariaDB testing framework, as well as which branch to target for your contributions.
Help
More help is available from the Maria Discuss mailing list https://lists.mariadb.org/postorius/lists/discuss.lists.mariadb.org/ and MariaDB's Zulip instance, https://mariadb.zulipchat.com/
Licensing
MariaDB is specifically available only under version 2 of the GNU General Public License (GPLv2). (I.e. Without the "any later version" clause.) This is inherited from MySQL. Please see the README file in the MySQL distribution for more information.
License information can be found in the COPYING file. Third party license information can be found in the THIRDPARTY file.
Bug Reports
Bug and/or error reports regarding MariaDB should be submitted at: https://jira.mariadb.org
For reporting security vulnerabilities see: https://mariadb.org/about/security-policy/
The code for MariaDB, including all revision history, can be found at: https://github.com/MariaDB/server