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https://dev.mysql.com/doc/internals/en/select-select-result.html
This class has a very important role in SELECT performance with select_result class and classes inherited from it (usually called with a select_ prefix). The key methods in this class are the following: send_fields sends given item list headers ...
https://dev.mysql.com/doc/internals/en/select-simple.html
For performing single primary select, SELECT uses the mysql_select function, which does: allocate JOIN JOIN::prepare JOIN::optimize JOIN::exec JOIN::cleanup In previous versions of MySQL, all SELECT operations were performed with the help of this ...
https://dev.mysql.com/doc/internals/en/select-union.html
if this is the first call, call JOIN::optimize else JOIN::reinit and then JOIN::exec for all SELECTs (select_union will write a result for the temporary table). We will need this object to store in every JOIN structure link on it, but we have not ...
https://dev.mysql.com/doc/internals/en/tracing-memory-usage.html
It is extended (with realloc()) as optimization progresses and appends data to it. The optimizer_trace_max_mem_size variable sets a limit on the total amount of memory used by all currently remembered traces: If this limit is reached, the current ...
https://dev.mysql.com/doc/internals/en/transformation-scalar-in.html
The scalar IN subquery will be replaced with an Item_in_optimizer item. If left expression (cache) is NULL, then Item_in_optimizer returns NULL, else it evaluates Item_in_subselect. This reference informs Item_in_optimizer whether item (t2.a) is ...
https://dev.mysql.com/doc/internals/en/variation-of-storage-engine.html
Therefore tests focussed on permissions, optimizer strategies, column data types etc. Checks of the INFORMATION_SCHEMA The storage engines to be used for information_schema tables are hardcoded. when selecting on INFORMATION_SCHEMA tables should ...
https://dev.mysql.com/doc/internals/en/x-protocol-implementation-implementation-notes.html
vectored io combines the best of both approaches and sends multiple buffers to the OS in one syscall and OS can optimize sending multiple buffers in on TCP packet. Topics in this section: Client Server Client and Server implementations of the ...
https://dev.mysql.com/doc/mysql-installer/en/server-type-network.html
Manual Prevents MySQL Installer from attempting to optimize the server installation, and instead, sets the default values to the server variables included in the my.ini configuration file. Server Configuration Type Choose the MySQL server ...
https://dev.mysql.com/doc/mysqld-version-reference/en/keywords-5-7.html
This section provides information about keywords and reserved words in MySQL 5.7. MySQL 5.7 Keywords and Reserved Words MySQL 5.7 New Keywords and Reserved Words MySQL 5.7 Removed Keywords and Reserved Words MySQL 5.7 Keywords and Reserved Words ...
https://dev.mysql.com/doc/mysqld-version-reference/en/keywords-8-0.html
This section provides information about keywords and reserved words in MySQL 8.0. MySQL 8.0 Keywords and Reserved Words MySQL 8.0 New Keywords and Reserved Words MySQL 8.0 Removed Keywords and Reserved Words MySQL 8.0 Keywords and Reserved Words ...