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https://dev.mysql.com/doc/refman/9.7/en/optimizing-innodb-queries.html
When an index contains unnecessary data, the I/O to read this data and memory to cache it reduce the performance and scalability of the server. To tune queries for InnoDB tables, create an appropriate set of indexes on each table. Follow these ...
https://dev.mysql.com/doc/refman/9.7/en/out-of-memory.html
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). Is it reasonable that it should return so many rows? If not, correct the query and try again.
https://dev.mysql.com/doc/refman/9.7/en/out-of-range-and-overflow.html
If no restrictive modes are enabled, MySQL clips the value to the appropriate endpoint of the column data type range and stores the resulting value instead. When an out-of-range value is assigned to an integer column, MySQL stores the value ...
https://dev.mysql.com/doc/refman/9.7/en/partitioning-limitations-storage-engines.html
In MySQL 9.7, partitioning support is not actually provided by the MySQL Server, but rather by a table storage engine's own or native partitioning handler. In MySQL 9.7, only the InnoDB and NDB storage engines provide native partitioning handlers.
https://dev.mysql.com/doc/refman/9.7/en/partitioning-management-range-list.html
DROP PARTITION is not reported by the server as it would be by the equivalent DELETE query. Adding and dropping of range and list partitions are handled in a similar fashion, so we discuss the management of both sorts of partitioning in this ...
https://dev.mysql.com/doc/refman/9.7/en/partitioning-range.html
A table that is partitioned by range is partitioned in such a way that each partition contains rows for which the partitioning expression value lies within a given range. Ranges should be contiguous but not overlapping, and are defined using the ...
https://dev.mysql.com/doc/refman/9.7/en/performance-schema-clone-progress-table.html
The clone_progress table has these columns: ID A unique cloning operation identifier in the current MySQL server instance. The clone_progress table shows progress information for the current or last executed cloning operation only. The stages of a ...
https://dev.mysql.com/doc/refman/9.7/en/performance-schema-cond-instances-table.html
The cond_instances table lists all the conditions seen by the Performance Schema while the server executes. A condition is a synchronization mechanism used in the code to signal that a specific event has happened, so that a thread waiting for this ...
https://dev.mysql.com/doc/refman/9.7/en/performance-schema-consumer-filtering.html
If you disable a consumer, the server does not spend time maintaining destinations for that consumer. To enable or disable a consumer, set its ENABLED value to YES or NO. For example, if you do not care about historical event information, disable ...
https://dev.mysql.com/doc/refman/9.7/en/performance-schema-file-instances-table.html
To list all the files currently opened by the server, use WHERE OPEN_COUNT > 0. The file_instances table lists all the files seen by the Performance Schema when executing file I/O instrumentation. If a file on disk has never been opened, it is not ...