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https://dev.mysql.com/doc/refman/8.4/en/innodb-online-ddl-limitations.html
OPTIMIZE TABLE for an InnoDB table is mapped to an ALTER TABLE operation to rebuild the table and update index statistics and free unused space in the clustered index. The following limitations apply to online DDL operations: The table is copied ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-performance-midpoint_insertion.html
To help you gauge the effect of setting these parameters, the SHOW ENGINE INNODB STATUS statement reports buffer pool statistics. Rather than using a strict LRU algorithm, InnoDB uses a technique to minimize the amount of data that is brought into ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-restrictions-limitations.html
mysql> CREATE TABLE t1 (c1 INT, db_row_id INT) ENGINE=INNODB; ERROR 1166 (42000): Incorrect column name 'db_row_id' SHOW TABLE STATUS does not provide accurate statistics for InnoDB tables except for the physical size reserved by the table. This ...
https://dev.mysql.com/doc/refman/8.4/en/memory-storage-engine.html
The MEMORY storage engine (formerly known as HEAP) creates special-purpose tables with contents that are stored in memory. Because the data is vulnerable to crashes, hardware issues, or power outages, only use these tables as temporary work areas ...
https://dev.mysql.com/doc/refman/8.4/en/myisam-check.html
myisamchk -e -i tbl_name This is like the previous command, but the -i option tells myisamchk to print additional statistical information. To check a MyISAM table, use the following commands: myisamchk tbl_name This finds 99.99% of all errors. What ...
https://dev.mysql.com/doc/refman/8.4/en/myisamchk-check-options.html
--information, -i Command-Line Format --information Print informational statistics about the table that is checked. myisamchk supports the following options for table checking operations: --check, -c Command-Line Format --check Check the table for ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-event-reports.html
Each reportable event can be distinguished according to three different criteria: Category: This can be any one of the following values: STARTUP, SHUTDOWN, STATISTICS, CHECKPOINT, NODERESTART, CONNECTION, ERROR, or INFO. In this section, we discuss ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-information-schema-tables.html
Additional statistical and other data about NDB Cluster transactions, operations, threads, blocks, and other aspects of performance can be obtained from the tables in the ndbinfo database. Two INFORMATION_SCHEMA tables provide information that is ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-limitations-performance.html
The Records in range statistic is available but is not completely tested or officially supported. The following performance issues are specific to or especially pronounced in NDB Cluster: Range scans. There are query performance issues due to ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-limitations-syntax.html
In such cases, statistical information is not generated, which means a nonoptimal execution plan may be selected. Some SQL statements relating to certain MySQL features produce errors when used with NDB tables, as described in the following list: ...