https://dev.mysql.com/thread-pool-tuning.html
This section provides guidelines on setting thread pool system variables for best performance, measured using a metric such as transactions per second. Our experience in testing the thread pool indicates the following: If the primary storage engine ...
https://dev.mysql.com/time-zone-support.html
It remains true that literal temporal values having a time part that ends with :59:60 or :59:61 are considered invalid. This section describes the time zone settings maintained by MySQL, how to load the system tables required for named time ...
https://dev.mysql.com/timestamp-lookups.html
It remains true that index-using queries match the converted search value to a single value in the UTC index entries, rather than matching multiple UTC values that convert to the search value in the session time zone. Temporal values are stored in ...
https://dev.mysql.com/truncate-table.html
This is true even for MyISAM and InnoDB, which normally do not reuse sequence values. Logically, TRUNCATE TABLE is similar to a DELETE statement that deletes all rows, or a sequence of DROP TABLE and CREATE TABLE statements. To achieve high ...
https://dev.mysql.com/tutorial.html
This chapter provides a tutorial introduction to MySQL by showing how to use the mysql client program to create and use a simple database. mysql (sometimes referred to as the “terminal monitor” or just “monitor”) is an interactive program ...
https://dev.mysql.com/type-conversion.html
When an operator is used with operands of different types, type conversion occurs to make the operands compatible. For example, MySQL automatically converts strings to numbers as necessary, and vice versa. mysql> SELECT 1+'1'; -> 2 mysql> SELECT ...
https://dev.mysql.com/update.html
where_condition is an expression that evaluates to true for each row to be updated. UPDATE is a DML statement that modifies rows in a table. An UPDATE statement can start with a WITH clause to define common table expressions accessible within the ...
https://dev.mysql.com/upgrade-troubleshooting.html
The same is true if the new version of MySQL implements a built-in function with the same name as an existing stored function. A schema mismatch in a MySQL 5.7 instance between the .frm file of a table and the InnoDB data dictionary can cause an ...
https://dev.mysql.com/upgrading-what-is-upgraded.html
This is true whether the server or mysql_upgrade performs the step. Installing a new version of MySQL may require upgrading these parts of the existing installation: The mysql system schema, which contains tables that store information required by ...
https://dev.mysql.com/user-variables.html
You can store a value in a user-defined variable in one statement and refer to it later in another statement. This enables you to pass values from one statement to another. User variables are written as @var_name, where the variable name var_name ...
