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https://dev.mysql.com/doc/refman/8.4/en/innodb-compression-tuning.html
Most often, the internal optimizations described in InnoDB Data Storage and Compression ensure that the system runs well with compressed data. However, because the efficiency of compression depends on the nature of your data, you can make decisions ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-locks-set.html
A locking read, an UPDATE, or a DELETE generally set record locks on every index record that is scanned in the processing of an SQL statement. It does not matter whether there are WHERE conditions in the statement that would exclude the row. InnoDB ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-transaction-isolation-levels.html
Transaction isolation is one of the foundations of database processing. Isolation is the I in the acronym ACID; the isolation level is the setting that fine-tunes the balance between performance and reliability, consistency, and reproducibility of ...
https://dev.mysql.com/doc/refman/8.4/en/lock-tables.html
LOCK {TABLE | TABLES} tbl_name [[AS] alias] lock_type [, tbl_name [[AS] alias] lock_type] ... lock_type: { READ [LOCAL] | WRITE } UNLOCK {TABLE | TABLES} MySQL enables client sessions to acquire table locks explicitly for the purpose of cooperating ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-limitations-transactions.html
A number of limitations exist in NDB Cluster with regard to the handling of transactions. The NDBCLUSTER storage engine supports only the READ COMMITTED transaction isolation level. To ensure that a given transaction reads only before or after ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-handling-nulls.html
Partitioning in MySQL does nothing to disallow NULL as the value of a partitioning expression, whether it is a column value or the value of a user-supplied expression. Even though it is permitted to use NULL as the value of an expression that must ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-statement-digests.html
The MySQL server is capable of maintaining statement digest information. The digesting process converts each SQL statement to normalized form (the statement digest) and computes a SHA-256 hash value (the digest hash value) from the normalized ...
https://dev.mysql.com/doc/refman/8.4/en/stored-objects-security.html
Stored programs (procedures, functions, triggers, and events) and views are defined prior to use and, when referenced, execute within a security context that determines their privileges. The privileges applicable to execution of a stored object are ...
https://dev.mysql.com/doc/refman/8.4/en/user-variables.html
You can store a value in a user-defined variable in one statement and refer to it later in another statement. This enables you to pass values from one statement to another. User variables are written as @var_name, where the variable name var_name ...
https://dev.mysql.com/doc/relnotes/mysql/8.4/en/news-8-4-0.html
(Bug #36301441) Audit log filtering by type, using error as the type, did not work correctly. (Bug #36142157) Following an unplanned shutdown and restart, the file that was in use by the server for writing at the time may be broken or otherwise ...