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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.
https://dev.mysql.com/doc/internals/en/prepared-stored.html
The role of the parser is to create a set of objects to represent the query. Creation of an execution plan, including evaluation of an order of joins and initialization of methods to access the used tables. Let us start with a general description ...