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https://dev.mysql.com/doc/refman/8.4/en/group-replication-configuring-consistency-guarantees.html
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: ...
https://dev.mysql.com/doc/refman/8.4/en/group-replication-server-states.html
The Performance Schema table replication_group_members shows the state for each member in a group. If you see this status for other servers, it can also mean that the member where you query this table is part of a partition, where a subset of the ...
https://dev.mysql.com/doc/refman/8.4/en/index-btree-hash.html
One circumstance under which this occurs is when the optimizer estimates that using the index would require MySQL to access a very large percentage of the rows in the table. (In this case, a table scan is likely to be much faster because it requires ... 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 hash ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-buffer-pool-in-core-file.html
The following table shows configuration and MADV_DONTDUMP support scenarios that determine whether core files are generated and whether they include buffer pool pages. The following table provides size reduction examples that you might see for a 1GB ... A core file records the status and memory image of a running ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-deadlock-detection.html
InnoDB is aware of table locks if innodb_table_locks = 1 (the default) and autocommit = 0, and the MySQL layer above it knows about row-level locks. Otherwise, InnoDB cannot detect deadlocks where a table lock set by a MySQL LOCK TABLES statement or ... When deadlock detection is enabled (the default), InnoDB automatically detects transaction deadlocks and rolls back a transaction or transactions to break the ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-disk-management.html
This section discusses the main considerations for I/O and disk space with the default kind of MySQL tables (also known as InnoDB tables): Controlling the amount of background I/O used to improve query performance. Organizing tables into many small ... As a DBA, you must manage disk I/O to keep the I/O subsystem from becoming saturated, and manage disk space to avoid filling up storage ...
https://dev.mysql.com/doc/refman/8.4/en/keyring-key-types.html
Table 8.31, “General Keyring Key Length Limits” shows the general key-length limits. (The lower limits for keyring_aws are imposed by the AWS KMS interface, not the keyring functions.) For keyring plugins, Table 8.32, “Keyring Plugin Key Types ... MySQL Keyring supports keys of different types (encryption algorithms) and lengths: The available key types depend on which keyring plugin is ...
https://dev.mysql.com/doc/refman/8.4/en/locking-issues.html
MySQL manages contention for table contents using locking: Internal locking is performed within the MySQL server itself to manage contention for table contents by multiple threads. External locking occurs when the server and other programs lock ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-logging-management-commands.html
The following table describes the default setting (for all data nodes) of the cluster log category threshold. Table 25.26 Cluster log categories, with default threshold setting Category Default threshold (All data nodes) STARTUP 7 SHUTDOWN 7 ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndb-innodb-engines.html
For those unaccustomed to working with NDB, unexpected behaviors can arise due to its distributed nature with regard to transactions, foreign keys, table limits, and other characteristics. The NDB storage engine is implemented using a distributed, ...