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https://dev.mysql.com/doc/internals/en/full-text-search.html
MySQL uses Ranking with Vector Spaces for ordinary full-text queries. Rank, also known as relevance rank, also known as relevance measure, is a number that tells us how good a match is. Vector Space, which MySQL sometimes calls "natural language", ...
https://dev.mysql.com/doc/internals/en/mysys-directory.html
There are 125 *.c programs in this directory: array.c --- Dynamic array handling charset.c --- Using dynamic character sets, set default character set, ... For example, the main functions in my_getwd.c are described thus: "int my_getwd _A((string ...
https://dev.mysql.com/doc/internals/en/prepared-stored-statement-execution.html
The execution plan created at prepare stage is not saved (see Section 17.2, “Preparation of a Prepared Statement”), and at execute we simply create a new set of JOINs and then prepare and optimize it. Some optimizations damage the parsed tree, ... In order to call mysql_execute_command (the function that executes a statement) for a prepared statement and not damage its parse tree, we backup and restore the active Query_arena of ...
https://dev.mysql.com/doc/internals/en/select-steps.html
Every select is performed in these base steps: JOIN::prepare Initialization and linking JOIN structure to st_select_lex. fix_fields() for all items (after fix_fields(), we know everything about item).
https://dev.mysql.com/doc/internals/en/transformations-all-any.html
ALL uses an inverted function, and all subqueries passed as arguments to Item_func_not_all (Item_func_not_all is a special NOT function used in optimization, see following). But before above transformation ability of independent ALL/ANY/SOME ...
https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-changelog-12-1-0-2-0.html
Functionality Added or Changed The compliance framework for MySQL Configuration Metrics is added in this release. Prev Up A.10 Changes in Oracle Enterprise Manager for MySQL Database 12.1.0.3.0 (2015-10-22) Home .
https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-changelog-12-1-0-4-0.html
The thresholds of the following metrics have been changed from critical to warning, and from warning to info: Table Cache Not Optimal Thread Cache Size Not Optimal Bugs Fixed Path-related errors occurred when using Oracle Enterprise Manager for ...
https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-compliance-performance-standard-rules.html
The following are the MySQL Performance Standard compliance rules: InnoDB Flush Method May Not Be Optimal InnoDB Log Buffer Flushed To Disk After Each Transaction InnoDB Flush Method May Not Be Optimal Description Different values for ...In some ...
https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-config-metric-innodbconfiguration-category.html
Change Buffering Whether InnoDB performs change buffering, an optimization that delays write operations to secondary indexes so that the I/O operations can be performed sequentially. Random Read Ahead Enabled Enables the random read-ahead technique ... Lists the InnoDB Configuration configuration metrics and provides a brief description of ...
https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-metric-mysqlserver-adminstatementactivity-category.html
Lists the Admin Statement Activity metrics and provides a brief description of each. Table 6.1 Admin Statement Activity Metrics NameDescriptionAdmin Commands (Delta) The total number of times a COM_PING, or COM_CHANGE_USER have executed on the ...