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https://dev.mysql.com/doc/internals/en/implementing-rnd-next-method.html
(The table definition is stored in the .frm file, and the optimizer and the handler are both able to access table metadata from the same source, its TABLE structure). After the table is initialized, the MySQL server will call the handler's ...
https://dev.mysql.com/doc/internals/en/myisam-directory.html
They are: mi_cache.c --- for reading records from a cache mi_changed.c --- a single routine for setting a "changed" flag (very short) mi_check.c --- for checking and repairing tables. Can be used to exactly replay a set of changes to a table.
https://dev.mysql.com/doc/internals/en/mysys-functions.html
Functions in mysys: (For flags see my_sys.h) int my_copy _A((const char *from, const char *to, myf MyFlags)); Copy file from from to to. int my_rename _A((const char *from, const char *to, myf MyFlags)); Rename file from from to to. int my_redel ...
https://dev.mysql.com/doc/internals/en/prepared-stored-statement-preparation.html
Some parts of the execution do not distinguish between preparation of a prepared statement and its execution and perform destructive optimizations of the parsed tree even during validation. As mentioned above, THD is currently a required argument ...
https://dev.mysql.com/doc/internals/en/prepared-stored.html
Let us start with a general description of the MySQL statement processing workflow in order to provide the reader with understanding of the problem of reexecution and vocabulary for the following sections. Conventional statements, that is, SQL ...
https://dev.mysql.com/doc/internals/en/preparing-for-index-use.html
The [custom-engine.html#custom-engine-api-reference-index_init index_init()] method is called before an index is used to allow the storage engine to perform any necessary preparation or optimization: int ha_foo::index_init(uint keynr, bool sorted) ...
https://dev.mysql.com/doc/internals/en/records-in-range.html
Used by optimizer to calculate cost of using a particular index. Purpose For the given range how many records are estimated to be in this range. Synopsis virtual ha_rows records_in_range ( inx, min_key, max_key); uint inx ; key_range * min_key ; ...
https://dev.mysql.com/doc/internals/en/select-derived.html
If it is not explain, then cleanup JOIN structures after execution (EXPLAIN needs data of optimization phase and cleanup them after whole query processing). Derived tables is the internal name for subqueries in the FROM clause. The processing of ...
https://dev.mysql.com/doc/internals/en/select-select-engine.html
If this is the first time, call JOIN::optimize and JOIN::exec(), else do nothing or JOIN::reinit()JOIN::exec() depending on type of subquery. subselect_single_select_engine: constructor allocate JOIN and store pointers on SELECT_LEX and JOIN.
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 ...