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https://dev.mysql.com/doc/refman/8.4/en/myisamchk-other-options.html
myisamchk supports the following options for actions other than table checks and repairs: --analyze, -a Command-Line Format --analyze Analyze the distribution of key values. To obtain information about the key distribution, use a myisamchk ...This ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-install-example-data.html
There are two key points to keep in mind: For a table to be replicated in the cluster, it must use the NDBCLUSTER storage engine. To specify this, use the ENGINE=NDBCLUSTER or ENGINE=NDB option when creating the table: CREATE TABLE tbl_name ... Note ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-dict-obj-tree.html
The dict_obj_tree table provides a tree-based view of table information from the dict_obj_info table. This is intended primarily for use in testing, but can be useful in visualizing hierarchies of NDB database objects. This means that you must know ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-programs-ndb-print-file.html
Options ndb_print_file supports the following options: --file-key, -K Command-Line Format --file-key=hex_data Supply file system encryption or decryption key from stdin, tty, or a my.cnf file. --file-key-from-stdin Command-Line Format ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-indexes.html
Most MySQL indexes (PRIMARY KEY, UNIQUE, INDEX, and FULLTEXT) are stored in B-trees. To find the MIN() or MAX() value for a specific indexed column key_col. This is optimized by a preprocessor that checks whether you are using WHERE key_part_N = ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-management.html
For a discussion of managing HASH and KEY partitions, see Section 26.3.2, “Management of HASH and KEY Partitions”. To change a table's partitioning scheme, it is necessary only to use the ALTER TABLE statement with a partition_options option, ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-subpartitions.html
Note SUBPARTITION BY HASH and SUBPARTITION BY KEY generally follow the same syntax rules as PARTITION BY HASH and PARTITION BY KEY, respectively. An exception to this is that SUBPARTITION BY KEY (unlike PARTITION BY KEY) does not currently support a ... Subpartitioning—also known as composite partitioning—is the further division of each partition in a partitioned ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-data-locks-table.html
Primary key values of the locked record are shown for a lock placed on the primary key index. Secondary index values of the locked record are shown with primary key values appended for a lock placed on a secondary index. If there is no primary key, ...For information about which lock requests are blocked by which held locks, see Section 29.12.13.2, “The data_lock_waits ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-wait-summary-tables.html
The Performance Schema maintains tables for collecting current and recent wait events, and aggregates that information in summary tables. Section 29.12.4, “Performance Schema Wait Event Tables” describes the events on which wait summaries are ...
https://dev.mysql.com/doc/refman/8.4/en/repair-table-optimization.html
Also, in addition to setting memory-allocation variables, increasing the myisam_max_sort_file_size system variable increases the likelihood that the repair uses the faster filesort method and avoids the slower repair by key cache method. Changing a ... REPAIR TABLE for MyISAM tables is similar to using myisamchk for repair operations, and some of the same performance optimizations apply: myisamchk has variables that control memory ...