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https://dev.mysql.com/doc/refman/8.4/en/information-schema-innodb-ft-index-table-table.html
The INNODB_FT_INDEX_TABLE table provides information about the inverted index used to process text searches against the FULLTEXT index of an InnoDB table. Before querying it, set the value of the innodb_ft_aux_table system variable to the name ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-innodb-metrics-table.html
With simple queries, you can check the overall health of the system. With more detailed queries, you can diagnose issues such as performance bottlenecks, resource shortages, and application issues. The INNODB_METRICS table provides a wide variety ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-optimizer-trace-table.html
The OPTIMIZER_TRACE table provides information produced by the optimizer tracing capability for traced statements. The OPTIMIZER_TRACE table has these columns: QUERY The text of the traced statement. MISSING_BYTES_BEYOND_MAX_MEM_SIZE Each ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-profiling-table.html
For example, the following queries are equivalent: SHOW PROFILE FOR QUERY 2; SELECT STATE, FORMAT(DURATION, 6) AS DURATION FROM INFORMATION_SCHEMA.PROFILING WHERE QUERY_ID = 2 ORDER BY SEQ; . Its contents correspond to the information produced by ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-views-table.html
For example, you might use the ANSI SQL mode to ensure MySQL correctly interprets the standard SQL concatenation operator, the double bar (||), in your queries. You must have the SHOW VIEW privilege to access this table. The VIEWS table has these ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-adaptive-hash.html
If a table fits almost entirely in main memory, a hash index speeds up queries by enabling direct lookup of any element, turning the index value into a sort of pointer. If InnoDB notices that queries could benefit from building a hash index, it does ... The adaptive hash index enables InnoDB to perform more like an in-memory database on systems with appropriate combinations of workload and sufficient memory for the buffer pool without sacrificing transactional features or ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-and-mysql-replication.html
It is possible to use replication in a way where the storage engine on the replica is not the same as the storage engine on the source. For example, you can replicate modifications to an InnoDB table on the source to a MyISAM table on the replica.
https://dev.mysql.com/doc/refman/8.4/en/innodb-information-schema-temp-table-info.html
INNODB_TEMP_TABLE_INFO provides information about user-created InnoDB temporary tables that are active in the InnoDB instance. It does not provide information about internal InnoDB temporary tables used by the optimizer. mysql> SHOW TABLES FROM ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-locks-set.html
It is important to create good indexes so that your queries do not scan more rows than necessary. A locking read, an UPDATE, or a DELETE generally set record locks on every index record that is scanned in the processing of an SQL statement. It does ...
https://dev.mysql.com/doc/refman/8.4/en/innodb-next-key-locking.html
The so-called phantom problem occurs within a transaction when the same query produces different sets of rows at different times. For example, if a SELECT is executed twice, but returns a row the second time that was not returned the first time, ...