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https://dev.mysql.com/doc/internals/en/heap-directory.html
All the MySQL table handlers (that is, the handlers that MySQL itself produces) have files with similar names and functions. Thus, this (heap) directory contains a lot of duplication of the myisam directory (for the MyISAM table handler). Such ...
https://dev.mysql.com/doc/internals/en/implementing-commit.html
To support COMMIT, create a method that matches this definition: int (*commit)(THD *thd, bool all); The method name is then listed in the commit (twelfth) entry of [custom-engine.html#custom-engine-handlerton the handlerton]. During a commit ...
https://dev.mysql.com/doc/internals/en/implementing-info-method.html
Prior to commencing a table scan, the [custom-engine.html#custom-engine-api-reference-info info()] method is called to provide extra table information to the optimizer. The information required by the optimizer is not given through return values ...
https://dev.mysql.com/doc/internals/en/implementing-rollback.html
To support ROLLBACK, create a method that matches this definition: int (*rollback)(THD *thd, bool all); The method name is then listed in the rollback (thirteenth) entry of [custom-engine.html#custom-engine-handlerton the handlerton]. Of the two ...
https://dev.mysql.com/doc/internals/en/innodb-field-contents.html
I made a table with this definition: CREATE TABLE T (FIELD1 VARCHAR(3), FIELD2 VARCHAR(3), FIELD3 VARCHAR(3)) Type=InnoDB; To understand what follows, you must know that table T has six columns — not three — because InnoDB automatically added ...
https://dev.mysql.com/doc/internals/en/logging-transactions-definitions.html
Note: N-writes include updates to N-tables, but also CREATE and DROP statements. To reason about logging different table types, we make some preliminary definitions. (D-T-table) A table that has a transactional engine is called a T-table.
https://dev.mysql.com/doc/internals/en/mismatch-of-focus-of-test-and-code-sequence.html
CREATE TABLE t1 ( id INT NOT NULL AUTO_INCREMENT, my_column VARCHAR(30), name LONGTEXT, PRIMARY KEY (id)); INSERT INTO t1(my_column,name) VALUES('2','two'); INSERT INTO t1(my_column,name) VALUES('1','one'); INSERT INTO t1(my_column,name) ...
https://dev.mysql.com/doc/internals/en/optimizer-index-join-type.html
For this query: SELECT column1, column2 FROM Table1; the optimizer will use join type = index only if the index has this definition: CREATE INDEX ... Consider this query: SELECT column1 FROM Table1; If column1 is indexed, then the optimizer may ...
https://dev.mysql.com/doc/internals/en/optimizer-index-merge-join-type.html
MySQL creates a cond_key_i condition for each of the usable keys. 7.2.2.5.1 Overview Index Merge is used when table condition can be converted to form: cond_1 OR cond_2 ... OR cond_N The conditions for conversion are that each cond_i can be used ...
https://dev.mysql.com/doc/internals/en/prepared-stored-procedure-execution.html
This arena happens to be also the permanent query arena of every instruction of the procedure, as the parser creates all instructions in the same arena. Execution of a stored procedure statement is similar to execution of a prepared statement.