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https://dev.mysql.com/doc/refman/8.4/en/ansi-diff-foreign-keys.html
The MATCH clause in the SQL standard controls how NULL values in a composite (multiple-column) foreign key are handled when comparing to a primary key in the referenced table. In that case, a (child table) row containing such a foreign key can be ...
https://dev.mysql.com/doc/workbench/en/wbcopytables.html
wbcopytables is a command-line utility included in MySQL Workbench that enables you to copy table data from a supported source database server to MySQL. wbcopytables can connect to the source database using either ODBC, the Python DBAPI, or the ...
https://dev.mysql.com/doc/internals/en/guided-tour-skeleton.html
Graphic: client <===== MESSAGE ====> server <======PACKETS ====> Example: INSERT INTO Table1 VALUES (1); To put it graphically, at this point there is a long-lasting connection between the client and one server thread. It consists of checking for ...
https://dev.mysql.com/doc/ndbapi/en/ndb-error-codes-schema-error.html
The following list enumerates all NDB errors of type SE (Schema error).
https://dev.mysql.com/doc/heatwave/en/mys-hw-advisor-data-placement.html
Data placement keys are used to partition table data among MySQL HeatWave nodes when loading tables. Partitioning table data by JOIN and GROUP BY key columns can improve query performance by avoiding costs associated with redistributing data among ...For more information about data placement keys, see Section 5.8.2, “Data Placement ...
https://dev.mysql.com/doc/refman/8.4/en/data-dictionary-schema.html
Data dictionary tables are protected and may only be accessed in debug builds of MySQL. However, MySQL supports access to data stored in data dictionary tables through INFORMATION_SCHEMA tables and SHOW statements. For an overview of the tables ...
https://dev.mysql.com/doc/refman/8.4/en/federated-usagenotes.html
The remote table that a FEDERATED table points to must exist before you try to access the table through the FEDERATED table. It is possible for one FEDERATED table to point to another, but you must be careful not to create a loop. A FEDERATED table ...The following items indicate features that the FEDERATED storage engine does and does not support: The remote server must be a MySQL ...
https://dev.mysql.com/doc/refman/8.4/en/mysql-cluster-limitations-transactions.html
NDBCLUSTER stores only part of a column value that uses any of MySQL's BLOB or TEXT data types in the table visible to MySQL; the remainder of the BLOB or TEXT is stored in a separate internal table that is not accessible to MySQL. This issue does ... A number of limitations exist in NDB Cluster with regard to the handling of ...
https://dev.mysql.com/doc/refman/8.4/en/upgrade-prerequisites.html
Preliminary checks: The following issues must not be present: There must be no tables that use obsolete data types or functions. Triggers must not have a missing or empty definer or an invalid creation context (indicated by the character_set_client, ... Before upgrading to the latest MySQL 8.4 release, ensure the upgrade readiness of your current MySQL 8.3 or MySQL 8.4 server instance by performing the preliminary checks described ...
https://dev.mysql.com/doc/mysql-em-plugin/en/myoem-config-metric-innodbconfiguration-category.html
Table 7.14 InnoDB Configuration Configuration Metrics NameDescriptionAdaptive Flushing Enabled Whether an heuristic to determine when to flush dirty pages in the buffer pool is used. Autoextend Increment The increment size (in MB) for extending the ... Lists the InnoDB Configuration configuration metrics and provides a brief description of ...