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https://dev.mysql.com/doc/refman/8.4/en/optimizing-myisam-bulk-data-loading.html
The main difference between automatic optimization and using the procedure explicitly is that you can let myisamchk allocate much more temporary memory for the index creation than you might want the server to allocate for index re-creation when it ... These performance tips supplement the general guidelines for fast inserts in Section 10.2.5.1, “Optimizing INSERT ...
https://dev.mysql.com/doc/refman/8.4/en/invisible-columns.html
For statements that insert or ignore new rows, or that replace or modify existing rows, based on values in a PRIMARY KEY or UNIQUE index, MySQL treats invisible columns the same as visible columns: Invisible columns participate in key value ...DDL ...An invisible column is normally hidden to queries, but can be accessed if explicitly ...
https://dev.mysql.com/doc/mysql-monitor/8.0/en/mem-query-analyzer-queries.html
For more information on Normalization and Statement Digests, see Performance Schema Statement Digests and Sampling. Note If you change the context, by selecting another MySQL instance from the All Targets menu, and the selected instance does not ...
https://dev.mysql.com/doc/refman/8.4/en/replication-features-transactions.html
You should also avoid using any statement that accesses both transactional (or temporary) and nontransactional tables and writes to any of them. The server uses these rules for binary logging: If the initial statements in a transaction are ...In ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-online-add-node-example.html
In addition, for each table, the ALTER TABLE statement should be followed by an OPTIMIZE TABLE to reclaim wasted space. REORGANIZE PARTITION statements for NDBCLUSTER tables created after the new data nodes have been added; data added to such tables ... In this section we provide a detailed example illustrating how to add new NDB Cluster data nodes online, starting with an NDB Cluster having 2 data nodes in a single node group and concluding with a cluster having 4 data nodes in 2 node ...
https://dev.mysql.com/doc/refman/8.4/en/derived-table-optimization.html
If a CTE is materialized, the optimizer automatically adds relevant indexes if it estimates that indexing can speed up access by the top-level statement to the CTE. During query execution, the optimizer may add an index to a derived table to speed ...The optimizer handles derived tables, view references, and common table expressions the same way: It avoids unnecessary materialization whenever possible, which enables pushing down conditions from the outer query to derived tables and produces more efficient execution ...
https://dev.mysql.com/doc/relnotes/mysql/8.4/en/news-8-4-1.html
(Bug #35352161) Running two concurrent OPTIMIZE TABLE statements on the same table with fulltext indexes and innodb_optimize_fulltext_only enabled sometimes caused the server to exit. (Bug #32631511) C API Notes C API applications stalled while ...
https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-metric-mysqlserver-handleractivity-category.html
Table 6.8 Handler Activity Metrics NameDescriptionCommit (Delta) The number of internal COMMIT statements. Prepare (Delta) The number of times the first entry in an index was read. Read First (Delta) The number of requests to read a row based on a ... Lists the Handler Activity metrics and provides a brief description of ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-innodb-buffer-page-table.html
IS_HASHED Whether a hash index has been built on this page. This column is applicable only to pages with a PAGE_TYPE value of INDEX. This can be the name of a clustered index or a secondary index. This column is applicable only to pages with a ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-params-ndbd.html
BuildIndexThreads: Number of threads to use for building ordered indexes during system or node restart. Setting this parameter to 0 disables multithreaded building of ordered indexes. DataMemory: Number of bytes on each data node allocated for ...