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https://dev.mysql.com/doc/refman/8.4/en/mathematical-functions.html
ABS(X) Returns the absolute value of X, or NULL if X is NULL. An implication of this is that ABS(-9223372036854775808) produces an error because the result cannot be stored in a signed BIGINT value. mysql> SELECT ABS(2); -> 2 mysql> SELECT ABS(-32); ...
https://dev.mysql.com/doc/refman/8.4/en/memory-use.html
For efficiency of cache management, the buffer pool is implemented as a linked list of pages; data that is rarely used is aged out of the cache, using a variation of the LRU algorithm. MySQL allocates buffers and caches to improve performance of ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-backup-using-management-client.html
Before starting a backup, make sure that the cluster is properly configured for performing one. If an existing backup_id value is used, the backup fails with the error Backup failed: file already exists. If used, the backup_id must follow ...
https://dev.mysql.com/doc/refman/8.4/en/nonpersistible-system-variables.html
SET PERSIST and SET PERSIST_ONLY enable global system variables to be persisted to the mysqld-auto.cnf option file in the data directory (see Section 15.7.6.1, “SET Syntax for Variable Assignment”). However, not all system variables can be ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-tp-thread-group-state-table.html
ALGORITHM The value of the thread_pool_algorithm system variable for the thread group. The tp_thread_group_state table has one row per thread group in the thread pool. Each row provides information about the current state of a group. The ...
https://dev.mysql.com/doc/refman/8.4/en/replica-logs-status.html
A replica server creates two replication metadata repositories, the connection metadata repository and the applier metadata repository. If binary log file position based replication is in use, when the replica restarts, it reads the two ...
https://dev.mysql.com/doc/refman/8.4/en/replication-options-reference.html
Slave_rows_last_search_algorithm_used: Search algorithm most recently used by this replica to locate rows for row-based replication (index, table, or hash scan). The following two sections provide basic information about the MySQL command-line ...
https://dev.mysql.com/doc/refman/8.4/en/replication-snapshot-method.html
Employing this method with a table using a storage engine that has complex caching or logging algorithms requires extra steps to produce a perfect “point in time” snapshot: the initial copy command could leave out cache information and logging ... If the source database contains existing data it is necessary to copy this data to each ...
https://dev.mysql.com/doc/refman/8.4/en/sha256-pluggable-authentication.html
In the name caching_sha2_password, “sha2” refers more generally to the SHA-2 class of encryption algorithms, of which 256-bit encryption is one instance. MySQL provides two authentication plugins that implement SHA-256 hashing for user account ...
https://dev.mysql.com/doc/refman/8.4/en/show-create-view.html
row *************************** View: v Create View: CREATE ALGORITHM=UNDEFINED DEFINER=`bob`@`localhost` SQL SECURITY DEFINER VIEW `v` AS select 1 AS `a`,2 AS `b` character_set_client: utf8mb4 collation_connection: utf8mb4_0900_ai_ci ... SHOW ...