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MariaDB server is a community developed fork of MySQL server. Started by core members of the original MySQL team, MariaDB actively works with outside developers to deliver the most featureful, stable, and sanely licensed open SQL server in the industry.
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in stored procedure. The problem was that MySQL used unnecessarily large amounts of memory if user variables were used as an argument to CONCAT or CONCAT_WS -- 16M per each user variable used. Technically, it happened because MySQL used the following allocation strategy for string functions to avoid multiple realloc() calls: in the virtual operation fix_length_and_dec() the attribute max_length was calculated as a sum of max_length values for each argument. Although this approach worked well for small (or fixed) data types, there could be a problem if there as a user variable among the arguments of a string function -- max_length of the function would be 16M (as the max_length of a user variable is 16M). Both CONCAT() and CONCAT_WS() functions suffer from this problem. The fix is to do not use meta-data for allocating memory. The following strategy is proposed instead: allocate the exact length of the result string at the first record, double the amount of memory allocated when it is required. No test case for this bug because there is no way to test memory consumption in a robust way with our test suite. sql/item_strfunc.cc: Implement memory-wise allocation strategy. |
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| BUILD | ||
| client | ||
| cmd-line-utils | ||
| config/ac-macros | ||
| dbug | ||
| Docs | ||
| extra | ||
| include | ||
| libmysql | ||
| libmysql_r | ||
| libmysqld | ||
| man | ||
| mysql-test | ||
| mysys | ||
| netware | ||
| plugin | ||
| pstack | ||
| regex | ||
| scripts | ||
| server-tools | ||
| sql | ||
| sql-bench | ||
| sql-common | ||
| storage | ||
| strings | ||
| support-files | ||
| tests | ||
| unittest | ||
| vio | ||
| win | ||
| zlib | ||
| .bzrignore | ||
| .cvsignore | ||
| CMakeLists.txt | ||
| configure.in | ||
| COPYING | ||
| EXCEPTIONS-CLIENT | ||
| Makefile.am | ||
| README | ||
This is a release of MySQL, a dual-license SQL database server. MySQL is brought to you by the MySQL team at MySQL AB. License information can be found in these files: - For GPL (free) distributions, see the COPYING file and the EXCEPTIONS-CLIENT file. - For commercial distributions, see the LICENSE.mysql file. For further information about MySQL or additional documentation, see: - The latest information about MySQL: http://www.mysql.com - The current MySQL documentation: http://dev.mysql.com/doc Some manual sections of special interest: - If you are migrating from an older version of MySQL, please read the "Upgrading from..." section first! - To see what MySQL can do, take a look at the features section. - For installation instructions, see the Installing and Upgrading chapter. - For the new features/bugfix history, see the Change History appendix. - For the currently known bugs/misfeatures (known errors) see the Problems and Common Errors appendix. - For a list of developers and other contributors, see the Credits appendix. A local copy of the MySQL Reference Manual can be found in the Docs directory in GNU Info format. You can also browse the manual online or download it in any of several formats at the URL given earlier in this file. ************************************************************ IMPORTANT: Bug or error reports should be sent to http://bugs.mysql.com.