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https://dev.mysql.com/doc/refman/8.4/en/innodb-locks-set.html
If you have no indexes suitable for your statement and MySQL must scan the entire table to process the statement, every row of the table becomes locked, which in turn blocks all inserts by other users to the table. LOCK TABLES sets table locks, but ... 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 ...
https://dev.mysql.com/doc/refman/8.4/en/install-component.html
A component provides services that are available to the server and other components; see Section 7.5, “MySQL Components”. INSTALL COMPONENT requires the INSERT privilege for the mysql.component system table because it adds a row to that table to ...[SET variable = expr [, variable = expr] ...] variable: { {GLOBAL | @@GLOBAL.} [component_prefix.]system_var_name | {PERSIST | @@PERSIST.} [component_prefix.]system_var_name } This statement installs one or more components, which become active ...
https://dev.mysql.com/doc/refman/8.4/en/installation-layouts.html
MySQL Installation Layout on Microsoft Windows Section 2.8.3, “MySQL Layout for Source Installation” Table 2.3, “MySQL Installation Layout for Generic Unix/Linux Binary Package” Table 2.13, “MySQL Installation Layout for Linux RPM Packages ... The installation layout differs for different installation types (for example, native packages, binary tarballs, and source tarballs), which can lead to confusion when managing different systems or using different installation ...
https://dev.mysql.com/doc/refman/8.4/en/invisible-indexes.html
MySQL supports invisible indexes; that is, indexes that are not used by the optimizer. Using the SET_VAR optimizer hint to update the value of optimizer_switch temporarily, you can enable invisible indexes for the duration of a single query only, ...The feature applies to indexes other than primary keys (either explicit or ...
https://dev.mysql.com/doc/refman/8.4/en/large-page-support.html
In MySQL, large pages can be used by InnoDB, to allocate memory for its buffer pool and additional memory pool. Standard use of large pages in MySQL attempts to use the largest size supported, up to 4MB. MySQL also supports the Linux implementation ... Some hardware and operating system architectures support memory pages greater than the default (usually ...
https://dev.mysql.com/doc/refman/8.4/en/log-destinations.html
MySQL Server provides flexible control over the destination of output written to the general query log and the slow query log, if those logs are enabled. Possible destinations for log entries are log files or the general_log and slow_log tables in ...Setting this variable does not in itself enable the logs; they must be enabled ...
https://dev.mysql.com/doc/refman/8.4/en/mysqlbinlog-backup.html
By default, mysqlbinlog reads binary log files and displays their contents in text format. This enables you to examine events within the files more easily and to re-execute them (for example, by using the output as input to mysql). mysqlbinlog can ...This capability enables you to easily back up a binary log in its original ...
https://dev.mysql.com/doc/refman/8.4/en/out-of-memory.html
This causes it to use the mysql_use_result() C API function to retrieve the result set, which places less of a load on the client (but more on the server). Is it reasonable that it should return so many rows? If not, correct the query and try again.
https://dev.mysql.com/doc/refman/8.4/en/partitioning-key.html
Partitioning by key is similar to partitioning by hash, except that where hash partitioning employs a user-defined expression, the hashing function for key partitioning is supplied by the MySQL server. Note Tables using the NDB storage engine are ...NDB Cluster uses MD5() for this purpose; for tables using other storage engines, the server employs its own internal hashing ...
https://dev.mysql.com/doc/refman/8.4/en/password-logging.html
If such statements are logged by the MySQL server as written, passwords in them become visible to anyone with access to the logs. In particular, INSERT or UPDATE statements for the mysql.user system table that refer to literal passwords are logged ... Passwords can be written as plain text in SQL statements such as CREATE USER, GRANT and SET ...