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https://dev.mysql.com/doc/refman/8.4/en/alter-table-partition-operations.html
To delete rows from selected partitions, use the TRUNCATE PARTITION option. To verify that the rows were dropped, check the INFORMATION_SCHEMA.PARTITIONS table, using a query such as this one: SELECT PARTITION_NAME, TABLE_ROWS FROM ...
https://dev.mysql.com/doc/refman/8.4/en/backup-types.html
Logical backup tools include the mysqldump program and the SELECT ... This section describes the characteristics of different types of backups. Physical (Raw) Versus Logical Backups Physical backups consist of raw copies of the directories and ...
https://dev.mysql.com/doc/refman/8.4/en/bnl-bka-optimization.html
Engine-specific MRR functions perform index lookups for the submitted keys, get row IDs (or primary keys) from them, and then fetch rows for all these selected row IDs one by one by request from BKA algorithm. With the first scenario, a portion of ... In MySQL, a Batched Key Access (BKA) Join algorithm is available that uses both index access to the joined table and a join ...
https://dev.mysql.com/doc/refman/8.4/en/case.html
(The indentation used here in the ELSE clause is for purposes of clarity only, and is not otherwise significant.) DELIMITER | CREATE PROCEDURE p() BEGIN DECLARE v INT DEFAULT 1; CASE v WHEN 2 THEN SELECT v; WHEN 3 THEN SELECT 0; ELSE BEGIN END; END ... CASE case_value WHEN when_value THEN statement_list [WHEN when_value THEN statement_list] ...
https://dev.mysql.com/doc/refman/8.4/en/charset-applications.html
To select a character set and collation at server startup, use the --character-set-server and --collation-server options. To select a character set and collation if you configure and build MySQL from source, use the DEFAULT_CHARSET and ... For ...
https://dev.mysql.com/doc/refman/8.4/en/charset-database.html
Every database has a database character set and a database collation. The CREATE DATABASE and ALTER DATABASE statements have optional clauses for specifying the database character set and collation: CREATE DATABASE db_name [[DEFAULT] CHARACTER SET ...
https://dev.mysql.com/doc/refman/8.4/en/charset-unicode-utf8mb4.html
The utf8mb4 character set has these characteristics: Supports BMP and supplementary characters. utf8mb4 contrasts with the utf8mb3 character set, which supports only BMP characters and uses a maximum of three bytes per character: For a BMP ...
https://dev.mysql.com/doc/refman/8.4/en/charset.html
MySQL includes character set support that enables you to store data using a variety of character sets and perform comparisons according to a variety of collations. The default MySQL server character set and collation are utf8mb4 and ...
https://dev.mysql.com/doc/refman/8.4/en/clone-plugin-remote.html
mysql> SELECT FILE_NAME FROM INFORMATION_SCHEMA.FILES; Plugins that are active on the donor, including any keyring plugin, must also be active on the recipient. To view undo tablespace file names on the donor to ensure that they are unique, query ...
https://dev.mysql.com/doc/refman/8.4/en/compatibility.html
Selecting SQL Modes The MySQL server can operate in different SQL modes, and can apply these modes differently for different clients, depending on the value of the sql_mode system variable. This section describes how MySQL relates to the ANSI/ISO ...