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https://dev.mysql.com/doc/refman/8.0/en/explain-extended.html
As of MySQL 8.0.12, extended information is available for SELECT, DELETE, INSERT, REPLACE, and UPDATE statements. SHOW WARNINGS displays an empty result for other explainable statements (DELETE, INSERT, REPLACE, and UPDATE). The EXPLAIN statement ...
https://dev.mysql.com/doc/refman/8.0/en/explain-for-connection.html
To obtain the execution plan for an explainable statement executing in a named connection, use this statement: EXPLAIN [options] FOR CONNECTION connection_id; EXPLAIN FOR CONNECTION returns the EXPLAIN information that is currently being used to ...
https://dev.mysql.com/doc/refman/8.0/en/external-locking.html
In this case, if the server tries to update a table that myisamchk is using, the server waits for myisamchk to finish before it continues. If you do use external locking option to enable updates to MyISAM tables from many MySQL processes, do not ...
https://dev.mysql.com/doc/refman/8.0/en/faqs-innodb-change-buffer.html
What types of operations modify secondary indexes and result in change buffering? INSERT, UPDATE, and DELETE operations can modify secondary indexes. When is the change buffer flushed? Updated pages are flushed by the same flushing mechanism that ...
https://dev.mysql.com/doc/refman/8.0/en/federated-description.html
When you create a table using one of the standard storage engines (such as MyISAM, CSV or InnoDB), the table consists of the table definition and the associated data. When you create a FEDERATED table, the table definition is the same, but the ...
https://dev.mysql.com/doc/refman/8.0/en/group-replication-use-cases.html
There is no need for server failover, and the multi-source update everywhere nature ensures that even updates are not blocked in the event of a single server failure. Group Replication enables you to create fault-tolerant systems with redundancy by ...
https://dev.mysql.com/doc/refman/8.0/en/host-cache.html
If that is successful, the host name is updated with the resolved host name and the validation flag is set to true. (In this case, another DNS resolution attempt occurs the next time a client connects from this IP.) If an error occurs while ... The ...
https://dev.mysql.com/doc/refman/8.0/en/information-schema-columns-table.html
on update CURRENT_TIMESTAMP for TIMESTAMP or DATETIME columns that have the ON UPDATE CURRENT_TIMESTAMP attribute. The related ST_GEOMETRY_COLUMNS table provides information about table columns that store spatial data. The COLUMNS table has these ...
https://dev.mysql.com/doc/refman/8.0/en/innodb-compression-background.html
For extracting or updating the column values, MySQL also creates an uncompressed page in the buffer pool with the uncompressed data. Within the buffer pool, any updates to the uncompressed page are also re-written back to the equivalent compressed ... Because processors and cache memories have increased in speed more than disk storage devices, many workloads are ...
https://dev.mysql.com/doc/refman/8.0/en/innodb-compression-tuning-monitoring.html
A large number of compression operations overall (compared to the number of INSERT, UPDATE and DELETE operations in your application and the size of the database) could indicate that some of your compressed tables are being updated too heavily for ... Overall application performance, CPU and I/O utilization and the size of disk files are good indicators of how effective compression is for your ...