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https://dev.mysql.com/doc/internals/en/select-select-result.html
send_data sends given item list values as row of table of result. 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 ...
https://dev.mysql.com/doc/internals/en/start-stmt.html
When table is locked a statement is started by calling start_stmt instead of external_lock Parameters thd lock_type Return Values This method has no return values. Purpose Called at the beginning of a statement for transaction purposes. Synopsis ...
https://dev.mysql.com/doc/internals/en/strings-directory.html
Many of the files in this subdirectory are equivalent to well-known functions that appear in most C string libraries. On the other hand, some of the files are MySQL additions or improvements. Often the MySQL changes are attempts to optimize the ...
https://dev.mysql.com/doc/internals/en/subtests.html
At least in cases where your file contains many subtests Mark these subtests for better readability of the script Write also a message into the protocol. And please explain what each subtest checks, unless it is obvious.
https://dev.mysql.com/doc/internals/en/support-for-delete.html
The following example is from the CSV storage engine: int ha_tina::delete_row(const byte * buf) { DBUG_ENTER("ha_tina::delete_row"); statistic_increment(table->in_use->status_var.ha_delete_count, &LOCK_status); if (chain_append()) DBUG_RETURN(-1); ...For non-indexed storage engines the parameter can be ignored, but transactional storage engines may need to store the deleted data for rollback ...
https://dev.mysql.com/doc/internals/en/traceable-queries.html
They are: SELECT; INSERT or REPLACE (with VALUES or SELECT); UPDATE/DELETE and their multi-table variants; all the previous ones prefixed by EXPLAIN; SET (unless it manipulates the optimizer_trace system variable); DO; DECLARE/CASE/IF/RETURN ...If ...
https://dev.mysql.com/doc/internals/en/transactions-life-cycle.html
When a new connection is established, thd->transaction members are initialized to an empty state. If a statement uses any tables, all affected engines are registered in the statement engine list. The remaining rare cases, when the server explicitly ...In non-autocommit mode, the same engines are registered in the normal transaction ...
https://dev.mysql.com/doc/internals/en/transformations-all-any.html
ALL/ANY/SOME use the same algorithm (and the same method of Item_in_subselect) as scalar IN, but use a different function instead of =. ANY/SOME use the same function that was listed after the left expression. ALL uses an inverted function, and all ...
https://dev.mysql.com/doc/internals/en/tuning-trace-purging.html
The SET statement has the following effects: All remembered traces are cleared A later SELECT on the OPTIMIZER_TRACE table returns the first LIMIT traces of the OFFSET oldest remembered traces (if OFFSET ≥ 0), or the first LIMIT traces of the ...
https://dev.mysql.com/doc/internals/en/variation-of-protocol-option.html
We have a lot of tests running very similar and extremely simple SQL just for the creation of a situation to be tested, check of table content, etc. It is usual to run tests with and without the mysql-test-run.pl startup option "--ps-protocol". And ...