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https://dev.mysql.com/doc/refman/8.4/en/obtaining-loadable-function-information.html
The Performance Schema user_defined_functions table contains information about the currently installed loadable functions: SELECT * FROM performance_schema.user_defined_functions; The mysql.func system table also lists installed loadable functions, ...This difference makes user_defined_functions preferable to mysql.func for checking which loadable functions are ...
https://dev.mysql.com/doc/refman/8.4/en/optimize-blob.html
Do not use this technique when the entire table is compressed by InnoDB or MyISAM. For a table with several columns, to reduce memory requirements for queries that do not use the BLOB column, consider splitting the BLOB column into a separate table ... When storing a large blob containing textual data, consider compressing it ...
https://dev.mysql.com/doc/refman/8.4/en/parenthesized-query-expressions.html
| TABLE | VALUES order_by_clause: ORDER BY as for SELECT limit_clause: LIMIT as for SELECT into_clause: INTO as for SELECT set_op: UNION | INTERSECT | EXCEPT MySQL 8.4 supports parenthesized query expressions according to the preceding syntax.
https://dev.mysql.com/doc/refman/8.4/en/partitioning-linear-hash.html
MySQL also supports linear hashing, which differs from regular hashing in that linear hashing utilizes a linear powers-of-two algorithm whereas regular hashing employs the modulus of the hashing function's value. We call this value V; it can be ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-queries.html
If the event tables contain both file and nonfile information, post-filtering is another way to see information only for file events. These indexes also improve performance for related objects, such as sys schema views that use those tables.
https://dev.mysql.com/doc/refman/8.4/en/pluggable-storage.html
Unplugging a Storage Engine To unplug a storage engine, use the UNINSTALL PLUGIN statement: UNINSTALL PLUGIN example; If you unplug a storage engine that is needed by existing tables, those tables become inaccessible, but are still present on disk ... MySQL Server uses a pluggable storage engine architecture that enables storage engines to be loaded into and unloaded from a running MySQL ...
https://dev.mysql.com/doc/refman/8.4/en/problems-with-float.html
The correct way to do floating-point number comparison is to first decide on an acceptable tolerance for differences between the numbers and then do the comparison against the tolerance value. Suppose that you execute the following statements: ...
https://dev.mysql.com/doc/refman/8.4/en/query-attributes.html
INSTALL COMPONENT loads the component, and also registers it in the mysql.component system table to cause it to be loaded during subsequent server startups. To uninstall the query_attributes component, use this statement: UNINSTALL COMPONENT ... The ...
https://dev.mysql.com/doc/refman/8.4/en/query-log.html
Each line that shows when a client connects also includes using connection_type to indicate the protocol used to establish the connection. connection_type is one of TCP/IP (TCP/IP connection established without SSL), SSL/TLS (TCP/IP connection ...
https://dev.mysql.com/doc/refman/8.4/en/replica-logs.html
The mysql.slave_master_info and mysql.slave_relay_log_info tables are created using the transactional storage engine InnoDB. Updates to the replica's applier metadata repository table are committed together with the transactions, meaning that the ...