Search Results
https://dev.mysql.com/doc/refman/8.4/en/mysqlcheck.html
The mysqlcheck client performs table maintenance: It checks, repairs, optimizes, or analyzes tables. Each table is locked and therefore unavailable to other sessions while it is being processed, although for check operations, the table is locked ...
https://dev.mysql.com/doc/refman/8.4/en/mysqlshow.html
The mysqlshow client can be used to quickly see which databases exist, their tables, or a table's columns or indexes. The same information can be obtained by using those statements directly. For example, you can issue them from the mysql client ...
https://dev.mysql.com/doc/refman/8.4/en/null-values.html
The NULL value means “no data.” NULL can be written in any lettercase. Be aware that the NULL value is different from values such as 0 for numeric types or the empty string for string types. For text file import or export operations performed ...
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, ...
https://dev.mysql.com/doc/refman/8.4/en/optimization-indexes.html
The best way to improve the performance of SELECT operations is to create indexes on one or more of the columns that are tested in the query. The index entries act like pointers to the table rows, allowing the query to quickly determine which rows ...
https://dev.mysql.com/doc/refman/8.4/en/optimize-table.html
OPTIMIZE TABLE reorganizes the physical storage of table data and associated index data, to reduce storage space and improve I/O efficiency when accessing the table. The exact changes made to each table depend on the storage engine used by that ...
https://dev.mysql.com/doc/refman/8.4/en/optimizing-innodb-many-tables.html
If you have configured non-persistent optimizer statistics (a non-default configuration), InnoDB computes index cardinality values for a table the first time that table is accessed after startup, instead of storing such values in the table. This ...
https://dev.mysql.com/doc/refman/8.4/en/optimizing-innodb-transaction-management.html
To optimize InnoDB transaction processing, find the ideal balance between the performance overhead of transactional features and the workload of your server. For example, an application might encounter performance issues if it commits thousands of ...
https://dev.mysql.com/doc/refman/8.4/en/optimizing-myisam-bulk-data-loading.html
These performance tips supplement the general guidelines for fast inserts in Section 10.2.5.1, “Optimizing INSERT Statements”. For a MyISAM table, you can use concurrent inserts to add rows at the same time that SELECT statements are running, ...
https://dev.mysql.com/doc/refman/8.4/en/optimizing-queries-myisam.html
Some general tips for speeding up queries on MyISAM tables: To help MySQL better optimize queries, use ANALYZE TABLE or run myisamchk --analyze on a table after it has been loaded with data. This updates a value for each index part that indicates ...