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https://dev.mysql.com/doc/internals/en/mysql-packet.html
If a MySQL client or server wants to send data, it: Splits the data into packets of size (224−1) bytes Prepends to each chunk a packet header Protocol::Packet Data between client and server is exchanged in packets of max 16MByte size. The number ...
https://dev.mysql.com/doc/internals/en/optimizer-constants-constant-tables.html
A MySQL constant is something more than a mere literal in the query. unique_not_null_column INT NOT NULL UNIQUE then this expression FROM Table1 ... These rules mean that a constant table has at most one row value. MySQL will evaluate a constant ...
https://dev.mysql.com/doc/internals/en/optimizer-definitions.html
A transformation occurs when one query is changed into another query which delivers the same result. This description uses a narrow definition: The optimizer is the set of routines which decide what execution path the DBMS should take for queries.
https://dev.mysql.com/doc/internals/en/optimizer-joins-access-methods.html
Bad join choices can cause more damage than bad choices in single-table searches, so MySQL developers have spent proportionally more time making sure that the tables in a query are joined in an optimal order and that optimal access methods (often ...
https://dev.mysql.com/doc/internals/en/parsing-key-information.html
Your storage engine will need to extract the information stored in the key and translate it into its internal index format to identify the row associated with the index. Many of the index methods pass a byte array named *key that identifies the ...
https://dev.mysql.com/doc/internals/en/plugins.html
You can build a plugin as static (compiled into the server) or dynamic (built as a dynamic library that must be installed using the INSTALL PLUGIN statement or the --plugin-load option before it can be used). Beginning with MySQL 5.1, the server ...
https://dev.mysql.com/doc/internals/en/required-server-code-patches.html
Currently procedures can only be compiled into the server staticly. There is no dynamic procedure for loading them dynamicly yet like we have for UDFs and plugins. The build system is not too clever about creating these symlinks for files added ...
https://dev.mysql.com/doc/internals/en/rnd-next.html
The Field structure for the table is the key to getting data into buf in a manner that will allow the server to understand it. Purpose Reads the next row from a table and returns it to the server. Synopsis virtual int rnd_next ( buf); byte * buf ; ...
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
We will need this object to store in every JOIN structure link on it, but we have not (yet) temporary table structure. Allocate JOIN structures and execute JOIN::prepare() for every SELECT to get full information about types of elements of SELECT ...