a7a933982d
Problem: ======= InnoDB persistent statistics doesn't take innodb_stats_method variable while calculating n_diff_pfx for the n-prefix index columns. Solution: ========= While calculating the persistent statistics, InnoDB consider all NULLS as different value when innodb_stats_method is set to NULLS_UNEQUAL or NULLS_IGNORED. InnoDB statistics depends on the value of "innodb_stats_method" variable when the statistics were last recalculated. dict_stats_analyze_index_level(), dict_stats_scan_page(), dict_stats_analyze_index_below_cur(), dict_stats_analyze_index_for_n_prefix(): All function accepts the parameter to indicate the innodb_stats_method. It also calculates the number of non-null key value for each level or leaf page dict_stats_index_set_n_diff(): calculates the number of non-null values similar to number of different key values. Append the non-default innodb_stats_method variable name for n_diff_pfx statistics description in mysql.innodb_index_stats. IndexScanStatistics: Structure to store the various statistical metric gathered during index scan fetch operation. This structure is being used in dict_stats_analyze_index_level() to fetch the statistics
Code status:
ci.appveyor.com
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/kb/en/mariadb-vs-mysql-features/
https://mariadb.com/kb/en/mariadb-versus-mysql-compatibility/
https://mariadb.com/kb/en/new-and-old-releases/
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