4194f7b605
The original query "SELECT IF(COUNT(a.`id`)>=0,'Y','N') FROM t" is transformed to "SELECT COUNT(a.`id`), IF(ref >= 0, 'Y', 'N') FROM t", where ref is Item_ref to "COUNT(a.`id`)", by split_sum_func(). Spider walks the item list twice, invoking spider_db_print_item_type(). The first invocation is in spider_create_group_by_handler() with str == NULL. The second one is in spider_group_by_handler::init_scan() with str != NULL. spider_db_print_item_type() prints nothing at the first invocation, and it prints item at the second invocation. However, at the second invocation, the above mentioned ref to "COUNT(a.`id`)" points to a field in a temporary table where the result will be stored. Thus, to look behind the item_ref, Spider need to generate the query earlier. A possible fix would be to generate a query to send in spider_create_group_by_handler(). However, the fix requires a considerable amount of changes of the Spider's GROUP BY handler. I'd like to avoid that. So, I fix the problem by not to use the GROUP BY handler when a query contains Item_ref whose table_name, name, and alias_name_used are not set. |
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BUILD | ||
client | ||
cmake | ||
dbug | ||
debian | ||
Docs | ||
extra | ||
include | ||
libmariadb@f6c3d9fd2a | ||
libmysqld | ||
libservices | ||
man | ||
mysql-test | ||
mysys | ||
mysys_ssl | ||
pcre | ||
plugin | ||
randgen/conf | ||
scripts | ||
sql | ||
sql-bench | ||
sql-common | ||
storage | ||
strings | ||
support-files | ||
tests | ||
unittest | ||
vio | ||
win | ||
wsrep | ||
zlib | ||
.clang-format | ||
.gitattributes | ||
.gitignore | ||
.gitmodules | ||
.travis.compiler.sh | ||
.travis.yml | ||
appveyor.yml | ||
BUILD-CMAKE | ||
CMakeLists.txt | ||
config.h.cmake | ||
configure.cmake | ||
COPYING | ||
CREDITS | ||
INSTALL-SOURCE | ||
INSTALL-WIN-SOURCE | ||
KNOWN_BUGS.txt | ||
README.md | ||
THIRDPARTY | ||
VERSION |
Code status:
MariaDB: drop-in replacement for MySQL
MariaDB is 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. 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 Foundation and the MariaDB Corporation, 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-features/
https://mariadb.com/kb/en/mariadb-versus-mysql-compatibility/
As MariaDB is a full replacement of MySQL, the MySQL manual at http://dev.mysql.com/doc is generally applicable.
Help:
More help is available from the Maria Discuss mailing list https://launchpad.net/~maria-discuss and the #maria IRC channel on Freenode.
Licensing:
NOTE:
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/
Bugs in the MySQL code can also be submitted at: https://bugs.mysql.com
The code for MariaDB, including all revision history, can be found at: https://github.com/MariaDB/server