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https://dev.mysql.com/doc/refman/9.7/en/condition-filtering.html
To control whether the optimizer considers additional filtering conditions, use the condition_fanout_filter flag of the optimizer_switch system variable (see Section 10.9.2, “Switchable Optimizations”). In join processing, prefix rows are those ...
https://dev.mysql.com/doc/refman/9.7/en/create-role.html
When the read_only system variable is enabled, CREATE ROLE additionally requires the CONNECTION_ADMIN privilege (or the deprecated SUPER privilege). CREATE ROLE [IF NOT EXISTS] role [, role ] ... CREATE ROLE creates one or more roles, which are ...
https://dev.mysql.com/doc/refman/9.7/en/deallocate-prepare.html
If too many prepared statements are created and not deallocated by either the DEALLOCATE PREPARE statement or the end of the session, you might encounter the upper limit enforced by the max_prepared_stmt_count system variable. {DEALLOCATE | DROP} ...
https://dev.mysql.com/doc/refman/9.7/en/deleting-from-related-tables.html
If the total length of the DELETE statement for related_table is more than the default value of the max_allowed_packet system variable, you should split it into smaller parts and execute multiple DELETE statements. You probably get the fastest ...
https://dev.mysql.com/doc/refman/9.7/en/group-replication-single-consensus-leader.html
By default, the group communication engine for Group Replication (XCom, a Paxos variant) operates using every member of the replication group as a leader. The group communication engine can use a single leader to drive consensus when the group is ...
https://dev.mysql.com/doc/refman/9.7/en/index-extensions.html
InnoDB automatically extends each secondary index by appending the primary key columns to it. Consider this table definition: CREATE TABLE t1 ( i1 INT NOT NULL DEFAULT 0, i2 INT NOT NULL DEFAULT 0, d DATE DEFAULT NULL, PRIMARY KEY (i1, i2), INDEX ...
https://dev.mysql.com/doc/refman/9.7/en/information-schema-innodb-cmp-per-index-table.html
You must enable the innodb_cmp_per_index_enabled system variable before performing the operations on compressed tables that you want to monitor. The INNODB_CMP_PER_INDEX and INNODB_CMP_PER_INDEX_RESET tables provide status information on operations ...
https://dev.mysql.com/doc/refman/9.7/en/information-schema-innodb-ft-being-deleted-table.html
Before querying it, set the value of the innodb_ft_aux_table system variable to the name (including the database name) of the table that contains the FULLTEXT index (for example, test/articles). The INNODB_FT_BEING_DELETED table provides a snapshot ...
https://dev.mysql.com/doc/refman/9.7/en/information-schema-innodb-ft-config-table.html
Before querying it, set the value of the innodb_ft_aux_table system variable to the name (including the database name) of the table that contains the FULLTEXT index (for example, test/articles). The INNODB_FT_CONFIG table provides metadata about ...
https://dev.mysql.com/doc/refman/9.7/en/information-schema-innodb-ft-default-stopword-table.html
This is not used if you override the default stopword processing with either the innodb_ft_server_stopword_table or the innodb_ft_user_stopword_table system variable. The INNODB_FT_DEFAULT_STOPWORD table holds a list of stopwords that are used by ...