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https://dev.mysql.com/doc/refman/8.4/en/delete.html
DELETE is a DML statement that removes rows from a table. A DELETE statement can start with a WITH clause to define common table expressions accessible within the DELETE. Single-Table Syntax DELETE [LOW_PRIORITY] [QUICK] [IGNORE] FROM tbl_name ...
https://dev.mysql.com/doc/refman/8.4/en/faqs-general.html
Why did MySQL version numbering skip versions 6 and 7 and go straight to 8.0? A.1.3. Does MySQL have a NOW() function with fractions of seconds? A.1.7. Which version of MySQL is production-ready (GA)? MySQL 9.4, 8.4, and 8.0 are actively supported ...
https://dev.mysql.com/doc/refman/8.4/en/group-replication-frequently-asked-questions.html
What is the maximum number of MySQL servers in a group? A group can consist of maximum 9 servers. Attempting to add another server to a group with 9 members causes the request to join to be refused. This limit has been identified from testing and ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-innodb-tablestats-table.html
The INNODB_TABLESTATS table provides a view of low-level status information about InnoDB tables. This data is used by the MySQL optimizer to calculate which index to use when querying an InnoDB table. This information is derived from in-memory data ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-best-practices.html
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 key. Use joins wherever data is pulled from multiple tables based on identical ID values from those ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-locks-set.html
A locking read, an UPDATE, or a DELETE generally set record locks on every index record that is scanned in the processing of an SQL statement. It does not matter whether there are WHERE conditions in the statement that would exclude the row. InnoDB ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-parameters.html
InnoDB Startup Options InnoDB System Variables System variables that are true or false can be enabled at server startup by naming them, or disabled by using a --skip- prefix. For example, to enable or disable the InnoDB adaptive hash index, you can ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-option-tables.html
The following list includes command-line options, system variables, and status variables applicable within mysqld when it is running as an SQL node in an NDB Cluster. For a reference to all command-line options, system variables, and status ...
https://dev.mysql.com/doc/refman/8.4/en/optimizing-innodb-bulk-data-loading.html
These performance tips supplement the general guidelines for fast inserts in Section 10.2.5.1, “Optimizing INSERT Statements”. When importing data into InnoDB, turn off autocommit mode, because it performs a log flush to disk for every insert.
https://dev.mysql.com/doc/refman/8.4/en/primary-key-optimization.html
The primary key for a table represents the column or set of columns that you use in your most vital queries. Query performance benefits from the NOT NULL optimization, because it cannot include any NULL values. With the InnoDB storage engine, the ...