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https://dev.mysql.com/doc/refman/8.4/en/other-vendor-data-types.html
To facilitate the use of code written for SQL implementations from other vendors, MySQL maps data types as shown in the following table. These mappings make it easier to import table definitions from other database systems into MySQL. If you create ...
https://dev.mysql.com/doc/refman/8.4/en/out-of-range-and-overflow.html
If no restrictive modes are enabled, MySQL clips the value to the appropriate endpoint of the column data type range and stores the resulting value instead. When an out-of-range value is assigned to an integer column, MySQL stores the value ...
https://dev.mysql.com/doc/refman/8.4/en/partitioning.html
See Section 28.3.21, “The INFORMATION_SCHEMA PARTITIONS Table”, for more information; for some examples of queries against this table, see Section 26.2.7, “How MySQL Partitioning Handles NULL”. Note Table partitioning differs from ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-connection-tables.html
When a client connects to the MySQL server, it does so under a particular user name and from a particular host. They differ in that, for grant tables, the host part of an account can be a pattern, whereas for Performance Schema tables, the host ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-instrument-filtering.html
Some of these queries use the LIKE operator and a pattern match instrument names. The setup_instruments table lists the available instruments: mysql> SELECT NAME, ENABLED, TIMED FROM performance_schema.setup_instruments; ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-instrument-naming.html
An instrument name consists of a sequence of elements separated by '/' characters. Example names: wait/io/file/myisam/log wait/io/file/mysys/charset wait/lock/table/sql/handler wait/synch/cond/mysys/COND_alarm ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-log-status-table.html
When the log_status table is queried, the server blocks logging and related administrative changes for just long enough to populate the table, then releases the resources. The log_status table provides information that enables an online backup tool ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-memory-model.html
Memory used depends on the load actually seen, not the load estimated or explicitly configured for. As the Performance Schema collects data, memory is allocated in the corresponding buffer. The buffer size is unbounded, and may grow with the load.
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-prepared-statements-instances-table.html
The Performance Schema provides instrumentation for prepared statements, for which there are two protocols: The binary protocol. This is accessed through the MySQL C API and maps onto underlying server commands as shown in the following table. C ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-rwlock-instances-table.html
The rwlock_instances table lists all the rwlock (read write lock) instances seen by the Performance Schema while the server executes. An rwlock is a synchronization mechanism used in the code to enforce that threads at a given time can have access ...