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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/mathematical-functions.html
One implication of this behavior is that for equal argument values, RAND(N) returns the same value each time, and thus produces a repeatable sequence of column values. It is a fast way to generate random numbers on demand that is portable between ...
https://dev.mysql.com/doc/refman/8.4/en/miscellaneous-optimization-tips.html
To fix any compression issues that occur with ARCHIVE tables, use OPTIMIZE TABLE. If possible, classify reports as “live” or as “statistical”, where data needed for statistical reports is created only from summary tables that are generated ... This section lists a number of miscellaneous tips for improving query processing speed: If your application makes several database requests to perform related updates, combining the statements into a stored routine can help ...
https://dev.mysql.com/doc/refman/8.4/en/multiple-column-indexes.html
If you specify the columns in the right order in the index definition, a single composite index can speed up several kinds of queries on the same table. If the table has a multiple-column index, any leftmost prefix of the index can be used by the ...
https://dev.mysql.com/doc/refman/8.4/en/myisamchk-memory.html
If you are going to use myisamchk on very large tables, you should first decide how much memory you want it to use. The following formula yields the amount of space required: (largest_key + row_pointer_length) * number_of_rows * 2 You can check the ...myisamchk uses no more memory than its memory-related variables are set ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-limitations-exclusive-to-cluster.html
NDB Cluster has the following limitations or restrictions with regard to binary logging: NDB Cluster cannot produce a binary log for tables having BLOB columns but no primary key. The following are limitations specific to the NDB storage engine: ...
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, ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-programs-ndb-top.html
This user must be able to read tables in the ndbinfo database (ndb_top uses information from ndbinfo.cpustat and related tables). The following table includes all options that are specific to the NDB Cluster program ndb_top. ndb_top displays ...
https://dev.mysql.com/doc/refman/8.4/en/network-namespace-support.html
Each namespace has its own IP addresses, network interfaces, routing tables, and so forth. Group Replication, only when using the MySQL communication stack to establish group communication connections. Network Namespace Monitoring For replication ...