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https://dev.mysql.com/doc/internals/en/optimizer-joins-access-methods.html
Bad join choices can cause more damage than bad choices in single-table searches, so MySQL developers have spent proportionally more time making sure that the tables in a query are joined in an optimal order and that optimal access methods (often ...The goal of the query optimizer is to find an optimal QEP among all such possible ...
https://dev.mysql.com/doc/internals/en/event-classes-and-types.html
Internally, the server uses C++ classes to represent binary log events. Type codes are associated with subclasses because class instance contents are written to binary or relay logs or are sent over the network from master to slave. In those ...
https://dev.mysql.com/doc/refman/8.4/en/upgrade-prerequisites.html
To check for these issues, execute this command: mysqlcheck -u root -p --all-databases --check-upgrade If mysqlcheck reports any errors, correct the issues. To identify such tables, execute this query: SELECT TABLE_SCHEMA, TABLE_NAME FROM ... Before ...
https://dev.mysql.com/doc/refman/8.4/en/x-plugin-options-system-variables.html
mysqlx_connect_timeout Command-Line Format --mysqlx-connect-timeout=# System Variable mysqlx_connect_timeout Scope Global Dynamic Yes SET_VAR Hint Applies No Type Integer Default Value 30 Minimum Value 1 Maximum Value 1000000000 Unit seconds The ...
https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-metric-mysqlserver-handleractivity-category.html
Delete (Delta) The number of times that rows have been deleted from tables. Mrr Init (Delta) The number of times the server uses a storage engine's own Multi-Range Read implementation for table access. Prepare (Delta) The number of times the first ... Lists the Handler Activity metrics and provides a brief description of ...
https://dev.mysql.com/doc/ndbapi/en/ndb-ndbtransaction.html
execute() is also equipped with an extra error handling parameter, which provides the two alternatives listed here: NdbOperation::AbortOnError: Any error causes the transaction to be aborted. NdbOperation::AO_IgnoreError: The transaction continues ...Several operations can be defined on the same NdbTransaction object, in which case they are executed in ...A transaction consists of a list of operations represented by the ...
https://dev.mysql.com/doc/mysql-monitor/8.0/en/mem-qanal-config-ui.html
Latency Maximum: the maximum execution time for an execution of this query. Maximum Time: the maximum time taken for an execution of this statement. Only queries executed within the displayed time period are displayed, using the Hours and Minutes ...
https://dev.mysql.com/doc/internals/en/event-meanings.html
INTVAR_EVENT Written every time a statement uses an AUTO_INCREMENT column or the LAST_INSERT_ID() function; precedes other events for the statement. RAND_EVENT Written every time a statement uses the RAND() function; precedes other events for the ...
https://dev.mysql.com/doc/internals/en/x-protocol-use-cases-use-cases.html
one row parse time to parse the prepare num_rows row execution time stays as before In case error reporting isn't a major topic one can combine multi-row INSERT with pipelining and reduce the per-row network overhead. Optimizing for Network ...
https://dev.mysql.com/doc/connectors/en/connector-odbc-reference-api.html
SQLParamData Yes ISO 92 Used in conjunction with SQLPutData to supply parameter data at execution time. SQLSetStmtOption Yes Deprecated Sets a statement option SQLGetStmtOption Yes Deprecated Returns the value of a statement option Table 5.8 ODBC ...