Search Results
https://dev.mysql.com/doc/refman/8.4/en/reloading-delimited-text-dumps.html
For backups produced with mysqldump --tab, each table is represented in the output directory by an .sql file containing the CREATE TABLE statement for the table, and a .txt file containing the table data. To reload a table, first change location ...
https://dev.mysql.com/doc/refman/8.4/en/replication-privilege-checks-account.html
Executing internal-use BINLOG statements to apply mysqlbinlog output, provided that the account also has permission for the tables and operations in those statements. Updating the system tables mysql.gtid_executed, mysql.slave_relay_log_info, ...
https://dev.mysql.com/doc/refman/8.4/en/revoke.html
To revoke all privileges from a user, use one of the following statements; either of these statements drops all global, database, table, column, and routine privileges for the named users or roles: REVOKE ALL PRIVILEGES, GRANT OPTION FROM ...[IGNORE ...
https://dev.mysql.com/doc/refman/8.4/en/select-optimization.html
Besides SELECT statements, the tuning techniques for queries also apply to constructs such as CREATE TABLE...AS SELECT, INSERT INTO...SELECT, and WHERE clauses in DELETE statements. Indexes are especially important for queries that reference ...
https://dev.mysql.com/doc/refman/8.4/en/server-option-variable-reference.html
The following table lists all command-line options, system variables, and status variables applicable within mysqld. The table lists command-line options (Cmd-line), options valid in configuration files (Option file), server system variables ...If ...
https://dev.mysql.com/doc/refman/8.4/en/server-shutdown.html
For additional information about thread termination, see Section 15.7.8.4, “KILL Statement”, in particular for the instructions about killed REPAIR TABLE or OPTIMIZE TABLE operations on MyISAM tables. If a thread is updating a nontransactional ... The server shutdown process takes place as follows: The shutdown process is ...
https://dev.mysql.com/doc/refman/8.4/en/show-triggers.html
SHOW TRIGGERS [{FROM | IN} db_name] [LIKE 'pattern' | WHERE expr] SHOW TRIGGERS lists the triggers currently defined for tables in a database (the default database unless a FROM clause is given). This statement returns results only for databases ...
https://dev.mysql.com/doc/refman/8.4/en/subqueries.html
They provide alternative ways to perform operations that would otherwise require complex joins and unions. For information about how the optimizer handles subqueries, see Section 10.2.2, “Optimizing Subqueries, Derived Tables, View References, and ...All subquery forms and operations that the SQL standard requires are supported, as well as a few features that are ...
https://dev.mysql.com/doc/refman/8.4/en/subquery-materialization.html
Materialization speeds up query execution by generating a subquery result as a temporary table, normally in memory. The first time MySQL needs the subquery result, it materializes that result into a temporary table. Any subsequent time the result is ... The optimizer uses materialization to enable more efficient subquery ...
https://dev.mysql.com/doc/refman/8.4/en/subquery-optimization-with-exists.html
row *************************** id: 2 select_type: DEPENDENT SUBQUERY table: t2 type: ref_or_null possible_keys: maybe_null_key key: maybe_null_key key_len: 5 ref: func rows: 2 Extra: Using where; Using index ... Triggered equalities can be used by ... Certain optimizations are applicable to comparisons that use the IN (or =ANY) operator to test subquery ...