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https://dev.mysql.com/doc/refman/8.4/en/forcing-innodb-recovery.html
If a high innodb_force_recovery value is required to start InnoDB, there may be corrupted data structures that could cause complex queries (queries containing WHERE, ORDER BY, or other clauses) to fail. In this case, you may only be able to run ...
https://dev.mysql.com/doc/refman/8.4/en/foreign-key-optimization.html
Depending on how the data is distributed, the queries might perform less I/O and take up less cache memory because the relevant columns are packed together on disk. (To maximize performance, queries try to read as few data blocks as possible from ...
https://dev.mysql.com/doc/refman/8.4/en/group-replication-configuring-consistency-guarantees.html
Permitted Queries Under Consistency Rules Although all writes are held when using BEFORE_ON_PRIMARY_FAILOVER consistency level, not all reads are blocked to ensure that you can still inspect the server while it is applying backlog after a promotion ... Although the Transaction Synchronization Points section explains that conceptually there are two synchronization points from which you can choose: on read or on write, these terms were a simplification and the terms used in Group Replication are: before and after transaction ...
https://dev.mysql.com/doc/refman/8.4/en/index-btree-hash.html
Understanding the B-tree and hash data structures can help predict how different queries perform on different storage engines that use these data structures in their indexes, particularly for the MEMORY storage engine that lets you choose B-tree or ...B-Tree Index Characteristics Hash Index Characteristics B-Tree Index Characteristics A B-tree index can be used for column comparisons in expressions that use the =, >, >=, <, <=, or BETWEEN ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-files-table.html
The FILES table provides information about the files in which MySQL tablespace data is stored. In NDB Cluster, this table also provides information about the files in which NDB Cluster Disk Data tables are stored. For additional information ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-innodb-buffer-page-table.html
The INNODB_BUFFER_PAGE table provides information about each page in the InnoDB buffer pool. For related usage information and examples, see Section 17.15.5, “InnoDB INFORMATION_SCHEMA Buffer Pool Tables”. Do not query this table on a ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-tables-table.html
The information_schema_stats_expiry system variable defines the period of time before cached table statistics expire. If there are no cached statistics or statistics have expired, statistics are retrieved from storage engines when querying table ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-benefits.html
Performance benefits are not limited to large tables with long-running queries. InnoDB tables have the following benefits: If the server unexpectedly exits because of a hardware or software issue, regardless of what was happening in the database at ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-data-encryption.html
This column can be queried to identify tables that reside in encrypted file-per-table tablespaces. InnoDB supports data-at-rest encryption for file-per-table tablespaces, general tablespaces, the mysql system tablespace, redo logs, and undo logs.
https://dev.mysql.com/doc/refman/8.4/en/innodb-performance-optimizer-statistics.html
This section describes how to configure persistent and non-persistent optimizer statistics for InnoDB tables. Persistent optimizer statistics are persisted across server restarts, allowing for greater plan stability and more consistent query ...