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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/ndbapi/en/overview-compatibility.html
In particular, if the schema on the cluster makes use of newer features not supported by the older API version does not support, it is possible that operations may be less than optimal or give rise to errors. The NDB API is now fairly mature, and ...
https://dev.mysql.com/doc/relnotes/connector-odbc/en/news-8-0-26.html
(Bug #32623180) A buffer overrun inside SQLColumns() caused Connector/ODBC to unexpectedly halt; memory management was optimized to prevent this problem. Deprecation and Removal Notes Functionality Added or Changed Bugs Fixed Deprecation and ...
https://dev.mysql.com/doc/relnotes/connector-python/en/news-8-0-32.html
This is now optimized by always using a single SET call, even for multiple parameters. Functionality Added or Changed Bugs Fixed Functionality Added or Changed Removed distutils support, which is deprecated in Python 3.10 and removed in Python 3.12. (WL #14861) Adopted type hint enforcement for function and class attributes with mypy; this is compliant with PEP 8 for module ...