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https://dev.mysql.com/doc/refman/8.0/en/optimizing-innodb-many-tables.html
If you have configured non-persistent optimizer statistics (a non-default configuration), InnoDB computes index cardinality values for a table the first time that table is accessed after startup, instead of storing such values in the table. This ...
https://dev.mysql.com/doc/refman/8.0/en/optimizing-innodb-transaction-management.html
For example, an application might encounter performance issues if it commits thousands of times per second, and different performance issues if it commits only every 2-3 hours. If a big transaction is slowing down server performance, rolling it back ... To optimize InnoDB transaction processing, find the ideal balance between the performance overhead of transactional features and the workload of your ...
https://dev.mysql.com/doc/refman/8.0/en/order-by-optimization.html
Increase the read_rnd_buffer_size variable value so that more rows are read at a time. For example: "filesort_summary": { "rows": 100, "examined_rows": 100, "number_of_tmp_files": 0, "peak_memory_used": 25192, "sort_mode": "<sort_key, ... This ...
https://dev.mysql.com/doc/refman/8.0/en/partitioning-limitations.html
Tables employing user-defined partitioning do not preserve the SQL mode in effect at the time that they were created. Therefore, a change in the SQL mode at any time after the creation of partitioned tables may lead to major changes in the behavior ... This section discusses current restrictions and limitations on MySQL partitioning ...
https://dev.mysql.com/doc/refman/8.0/en/partitioning-management-exchange.html
Exchanging Partitions Without Row-By-Row Validation To avoid time consuming validation when exchanging a partition with a table that has many rows, it is possible to skip the row-by-row validation step by appending WITHOUT VALIDATION to the ALTER ...
https://dev.mysql.com/doc/refman/8.0/en/pattern-matching.html
MySQL provides standard SQL pattern matching as well as a form of pattern matching based on extended regular expressions similar to those used by Unix utilities such as vi, grep, and sed. SQL pattern matching enables you to use _ to match any ...
https://dev.mysql.com/doc/refman/8.0/en/performance-schema-consumer-filtering.html
If you disable a consumer, the server does not spend time maintaining destinations for that consumer. If checked, they act as follows: events_statements_cpu, if NO, disables measurement of CPU_TIME. If YES, and the instrumentation is enabled and ...
https://dev.mysql.com/doc/refman/8.0/en/performance-schema-data-locks-table.html
Use the data_locks table to help diagnose performance problems that occur during times of heavy concurrent load. Lock ID formats are internal and subject to change at any time. For information about which lock requests are blocked by which held ...
https://dev.mysql.com/doc/refman/8.0/en/performance-schema-event-tables.html
For wait, stage, statement, and transaction events, the Performance Schema can monitor and store current events. In addition, when events end, the Performance Schema can store them in history tables. For each event type, the Performance Schema uses ...
https://dev.mysql.com/doc/refman/8.0/en/performance-schema-instrumentation-checking.html
It is always possible to determine what instruments the Performance Schema includes by checking the setup_instruments table. Changes to this code occur often, which also affects the set of instruments. It is not practical to list all the ...