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https://dev.mysql.com/doc/internals/en/filesort.html
This algorithm is described in the MySQL Reference manual; see ORDER BY Optimization.
https://dev.mysql.com/doc/internals/en/flush-tables.html
This will also ensure that all table changes are flushed to disk (but of course not as optimally as simply calling a sync for all tables)! When you do a FLUSH TABLES, the variable refresh_version is incremented. The idea of FLUSH TABLES is to force ...
https://dev.mysql.com/doc/internals/en/guided-tour-skeleton.html
Remember, by the way, that MySQL stores frequently-used select statements and result sets in memory as an optimization, but once the insert succeeds the stored sets are invalid. And now we're going to walk through something harder, namely the ...
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-index-read-last-method.html
The [custom-engine.html#custom-engine-api-reference-index_read_last index_read_last()] method works like [custom-engine.html#custom-engine-index-read index_read()] but finds the last row with the current key value or prefix: int ...
https://dev.mysql.com/doc/internals/en/implementing-records-in-range-method.html
The [custom-engine.html#custom-engine-api-reference-records_in_range records_in_range()] method is called by the optimizer to assist in choosing which index on a table to use for a query or join. It is defined as follows: ha_rows ...
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 ...