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https://dev.mysql.com/doc/refman/8.4/en/optimizer-hints.html
Conflicting hints In some cases hints can conflict, such as when JOIN_ORDER and JOIN_PREFIX have table orders that are impossible to apply at the same time: SELECT /*+ JOIN_ORDER(t1, t2) JOIN_PREFIX(t2, t1) */ ... HASH_JOIN, NO_HASH_JOIN: These ...
https://dev.mysql.com/doc/refman/8.4/en/optimizing-innodb-bulk-data-loading.html
If you have UNIQUE constraints on secondary keys, you can speed up table imports by temporarily turning off the uniqueness checks during the import session: SET unique_checks=0; ... If you have FOREIGN KEY constraints in your tables, you can speed ... These performance tips supplement the general guidelines for fast inserts in Section 10.2.5.1, “Optimizing INSERT ...
https://dev.mysql.com/doc/refman/8.4/en/optimizing-innodb-diskio.html
binlog_row_image If binary logs are on non-rotational storage and all tables have primary keys, consider setting this option to minimal to reduce logging. If you follow best practices for database design and tuning techniques for SQL operations, ...
https://dev.mysql.com/doc/refman/8.4/en/option-defaults-equals.html
You might try starting the server with --log-error my-errors, but this does not have the intended effect, as shown here: $> mysqld_safe --log-error my-errors & [1] 31357 $> 080111 22:53:31 mysqld_safe Logging to '/usr/local/mysql/var/tonfisk.err'.
https://dev.mysql.com/doc/refman/8.4/en/option-files.html
In an option file, you can have spaces around the = character, something that is not true on the command line. Note Any files to be found and included using the !includedir directive on Unix operating systems must have file names ending in .cnf. For ... Most MySQL programs can read startup options from option files (sometimes called configuration ...
https://dev.mysql.com/doc/refman/8.4/en/parenthesized-query-expressions.html
The maximum level of nesting supported is 63; this is after any simplifications or merges have been performed by the parser. parenthesized_query_expression: ( query_expression [order_by_clause] [limit_clause] ) [order_by_clause] [limit_clause] ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-limitations-partitioning-keys-unique-keys.html
The rule governing this relationship can be expressed as follows: All columns used in the partitioning expression for a partitioned table must be part of every unique key that the table may have. This section discusses the relationship of ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-limitations.html
This section discusses current restrictions and limitations on MySQL partitioning support. The following constructs are not permitted in partitioning expressions: Stored procedures, stored functions, loadable functions, or plugins. For a list of ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-maintenance.html
If you have deleted a large number of rows from a partition or if you have made many changes to a partitioned table with variable-length rows (that is, having VARCHAR, BLOB, or TEXT columns), you can use ALTER TABLE ... A number of table and ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning-management-exchange.html
In addition to the ALTER, INSERT, and CREATE privileges usually required for ALTER TABLE statements, you must have the DROP privilege to perform ALTER TABLE ... Table nt contains no foreign key references, and no other table has any foreign keys ...