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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 ...Log Control at Server Startup Log Control at Runtime Log Table Benefits and Characteristics Log Control at Server Startup The log_output system variable specifies the destination for log ...
https://dev.mysql.com/doc/refman/8.4/en/multiple-server-clients.html
On Unix, set the MYSQL_UNIX_PORT and MYSQL_TCP_PORT environment variables to point to the Unix socket file and TCP/IP port number before you start your clients. In a C program, you can specify the socket file or port number arguments in the ...Start ...
https://dev.mysql.com/doc/refman/8.4/en/myisampack.html
MySQL uses mmap() when possible to perform memory mapping on compressed tables. If mmap() does not work, MySQL falls back to normal read/write file operations. Please note the following: If the mysqld server was invoked with external locking ...When ...
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/nested-join-optimization.html
The following discussion refers to the join syntax described in Section 15.2.13.2, “JOIN Clause”. The syntax of table_factor is extended in comparison with the SQL Standard. The latter accepts only table_reference, not a list of them inside a ...
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/partitioning-range.html
However, MySQL must be able to evaluate the expression's return value as part of a LESS THAN (<) comparison. For example, when executing a query such as EXPLAIN SELECT COUNT(*) FROM employees WHERE separated BETWEEN '2000-01-01' AND '2000-12-31' ...
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 ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-statement-digests.html
The MySQL server is capable of maintaining statement digest information. Digesting occurs in the parser regardless of whether the Performance Schema is available, so that other features such as MySQL Enterprise Firewall and query rewrite plugins ...