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https://dev.mysql.com/doc/refman/8.4/en/innodb-best-practices.html
While you don't want to commit too often, you also don't want to issue huge batches of INSERT, UPDATE, or DELETE statements that run for hours without committing. To get exclusive write access to a set of rows, use the SELECT ... FOR UPDATE syntax ...Specify a primary key for every table using the most frequently queried column or columns, or an auto-increment value if there is no obvious primary ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-error-handling.html
You can make them less likely by doing as little work as possible between the first change to data during a transaction and the commit, so the locks are held for the shortest possible time and for the smallest possible number of rows. InnoDB ...
https://dev.mysql.com/doc/refman/8.4/en/myisam-crash-recovery.html
myisamchk works by creating a copy of the .MYD data file row by row. Normally the use of two --quick options is useful only if you have too little free disk space to perform a normal repair. This section describes how to check for and deal with ...
https://dev.mysql.com/doc/refman/8.4/en/show-create-database.html
If the SHOW statement includes an IF NOT EXISTS clause, the output too includes such a clause. row *************************** Database: test Create Database: CREATE DATABASE `test` /*!40100 DEFAULT CHARACTER SET utf8mb4 COLLATE utf8mb4_0900_ai_ci ... SHOW CREATE {DATABASE | SCHEMA} [IF NOT EXISTS] db_name Shows the CREATE DATABASE statement that creates the named ...
https://dev.mysql.com/doc/extending-mysql/8.4/en/plugin-types.html
For example, the plugin can see what statement produced a result set or was logged, the number of rows in a result, who the current user was for an operation, or the error code for failed operations. Such a plugin implements two capabilities: ...
https://dev.mysql.com/doc/internals/en/good-tests.html
There are a lot of strict rules and rules of thumb which may increase the quality of tests written for the tool pair mysqltest/mysqltest-run.pl (MTR). See the Writing Test Cases section of the MySQL Server Doxygen documentation, available at ...
https://dev.mysql.com/doc/internals/en/item-class.html
MySQL's Item class is defined in .../sql/item.h, and its subclasses are defined in .../sql/item*.h (that is, in item.h, item_cmpfunc.h, item_func.h, item_geofunc.h, item_row.h, item_strfunc.h, item_subselect.h, item_sum.h, item_timefunc.h). To us, ...
https://dev.mysql.com/doc/internals/en/select-union.html
Merging types of result fields and storing them in special Items (Item_type_holder) will be done in this loop, too. st_select_lex_unit::exec Delete rows from the temporary table if this is not the first call. We will need this object to store in ...
https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-performance-page-database-file-io.html
Rows for which the HOST column in the underlying Performance Schema table is NULL are assumed to be for background threads and are reported with a host name of background. Redo Log Waits Graphs the number of times the log buffer was too small and ...
https://dev.mysql.com/doc/heatwave/en/mys-hwaml-classification-score.html
You should also use a larger number of records for training and validation to get a valid score. mysql> SELECT @classification_score; +-----------------------+ | @classification_score | +-----------------------+ | 0.800000011920929 | ... After ...