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https://dev.mysql.com/doc/refman/8.4/en/differences-from-ansi.html
For example, in MySQL, privileges for a table are not automatically revoked when you delete a table. You must explicitly issue a REVOKE statement to revoke privileges for a table. We try to make MySQL Server follow the ANSI SQL standard and the ...
https://dev.mysql.com/doc/refman/8.4/en/distinct-optimization.html
DISTINCT combined with ORDER BY needs a temporary table in many cases. If you do not use columns from all tables named in a query, MySQL stops scanning any unused tables as soon as it finds the first match. Because DISTINCT may use GROUP BY, learn ...
https://dev.mysql.com/doc/refman/8.4/en/document-store-concepts.html
The most important differences between a document and the tables known from traditional relational databases are that the structure of a document does not have to be defined in advance, and a collection can contain multiple documents with different ... This section explains the concepts introduced as part of using MySQL as a document ...
https://dev.mysql.com/doc/refman/8.4/en/drop-server.html
Dropping a server for a table does not affect any FEDERATED tables that used this connection information when they were created. DROP SERVER [ IF EXISTS ] server_name Drops the server definition for the server named server_name. DROP SERVER is not ...
https://dev.mysql.com/doc/refman/8.4/en/drop-trigger.html
DROP TRIGGER requires the TRIGGER privilege for the table associated with the trigger. Triggers for a table are also dropped if you drop the table. DROP TRIGGER [IF EXISTS] [schema_name.]trigger_name This statement drops a trigger. If the schema is ...
https://dev.mysql.com/doc/refman/8.4/en/error-log.html
For example, if mysqld notices that a table needs to be automatically checked or repaired, it writes a message to the error log. Depending on error log configuration, error messages may also populate the Performance Schema error_log table, to ...
https://dev.mysql.com/doc/refman/8.4/en/execution-plan-information.html
Depending on the details of your tables, columns, indexes, and the conditions in your WHERE clause, the MySQL optimizer considers many techniques to efficiently perform the lookups involved in an SQL query. A query on a huge table can be performed ...The set of operations that the optimizer chooses to perform the most efficient query is called the “query execution plan”, also known as the EXPLAIN ...
https://dev.mysql.com/doc/refman/8.4/en/expressions.html
The following table shows the expected form of the expr argument for each unit value. This section lists the grammar rules that expressions must follow in MySQL and provides additional information about the types of terms that may appear in ...
https://dev.mysql.com/doc/refman/8.4/en/federated-storage-engine.html
Querying a local FEDERATED table automatically pulls the data from the remote (federated) tables. The FEDERATED storage engine lets you access data from a remote MySQL database without using replication or cluster technology. To include the ...
https://dev.mysql.com/doc/refman/8.4/en/group-replication-configuring-instances.html
The host name that the server is using for SQL client connections can be verified in the Member_host column of the Performance Schema table replication_group_members. Configuring group_replication_group_seeds sets the hostname and port of the group ... This section explains the configuration settings required for MySQL Server instances that you want to use for Group ...