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https://dev.mysql.com/doc/refman/8.4/en/partitioning-info.html
Methods of obtaining such information include the following: Using the SHOW CREATE TABLE statement to view the partitioning clauses used in creating a partitioned table. Using the SHOW TABLE STATUS statement to determine whether a table is ... This ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-management.html
There are a number of ways using SQL statements to modify partitioned tables; it is possible to add, drop, redefine, merge, or split existing partitions using the partitioning extensions to the ALTER TABLE statement. There are also ways to obtain ...For a discussion of managing HASH and KEY partitions, see Section 26.3.2, “Management of HASH and KEY ...
https://dev.mysql.com/doc/refman/8.4/en/replica-logs-status.html
The connection metadata repository is written to the slave_master_info table in the mysql system schema, and the applier metadata repository is written to the slave_relay_log_info table in the mysql system schema. A warning message is issued if ...
https://dev.mysql.com/doc/mysql-enterprise-backup/8.4/en/backup-capacity-options.html
--sleep=MS Command-Line Format --sleep=MS Type Numeric Default Value 0 Unit millisecond Specify the number in milliseconds to sleep after copying a certain amount of data from InnoDB tables. --skip-unused-pages Skip unused pages in tablespaces when ... These options limit the resources used by the backup process, in order to minimize backup overhead for busy or huge databases, or specify behaviors of the process when encountering resource ...
https://dev.mysql.com/doc/refman/8.4/en/known-issues.html
Even if you use lower_case_table_names=2 (which enables MySQL to remember the case used for databases and table names), MySQL does not remember the case used for database names for the function DATABASE() or within the various logs (on ... This ...
https://dev.mysql.com/doc/refman/8.4/en/alter-database.html
Encryption Option The ENCRYPTION option, defines the default database encryption, which is inherited by tables created in the database. The existing tables within it are part of the general mysql tablespace, which may be encrypted. All tables in the ...alter_option: { [DEFAULT] CHARACTER SET [=] charset_name | [DEFAULT] COLLATE [=] collation_name | [DEFAULT] ENCRYPTION [=] {'Y' | 'N'} | READ ONLY [=] {DEFAULT | 0 | 1} } ALTER DATABASE enables you to change the overall characteristics of a ...
https://dev.mysql.com/doc/refman/8.4/en/hash-joins.html
row *************************** id: 1 select_type: SIMPLE table: t1 partitions: NULL type: ALL possible_keys: NULL key: NULL key_len: NULL ref: NULL rows: 1 filtered: 100.00 Extra: NULL *************************** 2. row *************************** ...It is possible to control whether hash joins are employed using one of the BNL and NO_BNL optimizer hints, or by setting block_nested_loop=on or block_nested_loop=off as part of the setting for the optimizer_switch server system ...
https://dev.mysql.com/doc/refman/8.4/en/storage-engines.html
Storage engines are MySQL components that handle the SQL operations for different table types. InnoDB is the default and most general-purpose storage engine, and Oracle recommends using it for tables except for specialized use cases. (The CREATE ...
https://dev.mysql.com/doc/refman/8.4/en/trigger-syntax.html
Here is a simple example that associates a trigger with a table, to activate for INSERT operations. The trigger acts as an accumulator, summing the values inserted into one of the columns of the table. In this case, the trigger activates before each ... To create a trigger or drop a trigger, use the CREATE TRIGGER or DROP TRIGGER statement, described in Section 15.1.22, “CREATE TRIGGER Statement”, and Section 15.1.34, “DROP TRIGGER ...
https://dev.mysql.com/doc/refman/8.4/en/bnl-bka-optimization.html
In MySQL, a Batched Key Access (BKA) Join algorithm is available that uses both index access to the joined table and a join buffer. Benefits of BKA include improved join performance due to more efficient table scanning. Moreover, a join buffer can ...The BKA algorithm supports inner join, outer join, and semijoin operations, including nested outer ...