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https://dev.mysql.com/doc/refman/8.4/en/descending-indexes.html
MySQL supports descending indexes: DESC in an index definition is no longer ignored but causes storage of key values in descending order. Previously, indexes could be scanned in reverse order but at a performance penalty. A descending index can be ...
https://dev.mysql.com/doc/refman/8.4/en/explain-output.html
The EXPLAIN statement provides information about how MySQL executes statements. EXPLAIN returns a row of information for each table used in the SELECT statement. It lists the tables in the output in the order that MySQL would read them while ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-data-encryption.html
InnoDB supports data-at-rest encryption for file-per-table tablespaces, general tablespaces, the mysql system tablespace, redo logs, and undo logs. You can set an encryption default for schemas and general tablespaces; this permits DBAs to control ...
https://dev.mysql.com/doc/refman/8.4/en/merge-table-advantages.html
MERGE tables can help you solve the following problems: Easily manage a set of log tables. For example, you can put data from different months into separate tables, compress some of them with myisampack, and then create a MERGE table to use them as ...
https://dev.mysql.com/doc/refman/8.4/en/myisamchk-general-options.html
The options described in this section can be used for any type of table maintenance operation performed by myisamchk. The sections following this one describe options that pertain only to specific operations, such as table checking or repairing.
https://dev.mysql.com/doc/refman/8.4/en/myisamchk.html
The myisamchk utility gets information about your database tables or checks, repairs, or optimizes them. myisamchk works with MyISAM tables (tables that have .MYD and .MYI files for storing data and indexes). You can also use the CHECK TABLE and ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-limitations-syntax.html
Some SQL statements relating to certain MySQL features produce errors when used with NDB tables, as described in the following list: Temporary tables. Trying either to create a temporary table that uses the NDB storage engine or to alter an ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-indexes.html
Indexes are used to find rows with specific column values quickly. Without an index, MySQL must begin with the first row and then read through the entire table to find the relevant rows. If the table has an index for the columns in question, MySQL ...
https://dev.mysql.com/doc/refman/8.4/en/optimize-table.html
OPTIMIZE TABLE reorganizes the physical storage of table data and associated index data, to reduce storage space and improve I/O efficiency when accessing the table. The exact changes made to each table depend on the storage engine used by that ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-limitations.html
This section discusses current restrictions and limitations on MySQL partitioning support. The following constructs are not permitted in partitioning expressions: Stored procedures, stored functions, loadable functions, or plugins. For a list of ...