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https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-log-statistics.html
The NDB management client's CLUSTERLOG STATISTICS command can provide a number of useful statistics in its output. Counters providing information about the state of the cluster are updated at 5-second reporting intervals by the transaction ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-config-values.html
You can obtain output that is more specific, more detailed, or both by issuing the proper queries. The config_values table provides information about the current state of node configuration parameter values. Each row in the table corresponds to the ...
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-ndbinfo.html
All ndbinfo tables are read-only, and are generated on demand when queried. ndbinfo is a database containing information specific to NDB Cluster. This database contains a number of tables, each providing a different sort of data about NDB Cluster ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-nutshell.html
This release adds two system status variables providing information about accesses to the PROCESSLIST table, listed here: Deprecated_use_i_s_processlist_count provides a count of the number of references to the PROCESSLIST table in queries since the ... This section summarizes what has been added to, deprecated in, changed, and removed from MySQL 8.4 since MySQL ...
https://dev.mysql.com/doc/refman/8.4/en/optimization-indexes.html
You must find the right balance to achieve fast queries using the optimal set of indexes. The best way to improve the performance of SELECT operations is to create indexes on one or more of the columns that are tested in the query. The index ...
https://dev.mysql.com/doc/refman/8.4/en/optimize-blob.html
For a table with several columns, to reduce memory requirements for queries that do not use the BLOB column, consider splitting the BLOB column into a separate table and referencing it with a join query when needed. Rather than testing for equality ... When storing a large blob containing textual data, consider compressing it ...
https://dev.mysql.com/doc/refman/8.4/en/optimizer-statistics.html
The column_statistics data dictionary table stores histogram statistics about column values, for use by the optimizer in constructing query execution plans. The column_statistics table has these characteristics: The table contains statistics for ...
https://dev.mysql.com/doc/refman/8.4/en/optimizing-subqueries.html
See also Section 10.2.2, “Optimizing Subqueries, Derived Tables, View References, and Common Table Expressions”. Development is ongoing, so no optimization tip is reliable for the long term. The following list provides some interesting tricks ...
https://dev.mysql.com/doc/refman/8.4/en/out-of-memory.html
Is it reasonable that it should return so many rows? If not, correct the query and try again. This causes it to use the mysql_use_result() C API function to retrieve the result set, which places less of a load on the client (but more on the server).