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https://dev.mysql.com/doc/refman/8.4/en/innodb-file-defragmenting.html
Random insertions into or deletions from a secondary index can cause the index to become fragmented. Fragmentation means that the physical ordering of the index pages on the disk is not close to the index ordering of the records on the pages, or ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-ndbinfo-locks-per-fragment.html
The locks_per_fragment table provides information about counts of lock claim requests, and the outcomes of these requests on a per-fragment basis, serving as a companion table to operations_per_fragment and memory_per_fragment. This table also ...
https://dev.mysql.com/doc/refman/8.4/en/mysqldumpslow.html
The MySQL slow query log contains information about queries that take a long time to execute (see Section 7.4.5, “The Slow Query Log”). mysqldumpslow parses MySQL slow query log files and summarizes their contents. Normally, mysqldumpslow ...
https://dev.mysql.com/doc/refman/8.4/en/operator-precedence.html
Operator precedences are shown in the following list, from highest precedence to the lowest. Operators that are shown together on a line have the same precedence. When used as a comparison operator, it has the same precedence as <=>, >=, >, <=, <, ...
https://dev.mysql.com/doc/refman/8.4/en/optimize-character.html
For character and string columns, follow these guidelines: Use binary collation order for fast comparison and sort operations, when you do not need language-specific collation features. You can use the BINARY operator to use binary collation within ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-replication-asynchronous-connection-failover-table.html
This table holds the replica's source lists for each replication channel for the asynchronous connection failover mechanism. The asynchronous connection failover mechanism automatically establishes an asynchronous (source to replica) replication ...
https://dev.mysql.com/doc/refman/8.4/en/program-options.html
There are several ways to specify options for MySQL programs: List the options on the command line following the program name. This is common for options that apply to a specific invocation of the program. List the options in an option file that ...
https://dev.mysql.com/doc/refman/8.4/en/replication-gtids-assign-anon.html
You can set up replication channels to assign a GTID to replicated transactions that do not already have one. This feature enables replication from a source server that does not have GTIDs enabled and does not use GTID-based replication, to a ...
https://dev.mysql.com/doc/refman/8.4/en/replication-privilege-checks-account.html
The user account that is specified using the CHANGE REPLICATION SOURCE TO statement as the PRIVILEGE_CHECKS_USER account for a replication channel must have the REPLICATION_APPLIER privilege, otherwise the replication applier thread does not start.
https://dev.mysql.com/doc/mysql-cluster-manager/8.4/en/mcm-autotune.html
autotune [--dryrun] [--sequential-restart] [--writeload=writeload] template cluster_name writeload: {low|medium|high} template: {web|realtime|test} The command autotune a number of parameters for the cluster according to the specified values for ...