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https://dev.mysql.com/doc/refman/8.4/en/built-in-function-reference.html
The following table lists each built-in (native) function and operator and provides a short description of each one. For a table listing functions that are loadable at runtime, see Section 14.2, “Loadable Function Reference”. ->> Return value ...
https://dev.mysql.com/doc/refman/8.4/en/cast-functions.html
Table 14.15 Cast Functions and Operators Name Description Deprecated BINARY Cast a string to a binary string Yes CAST() Cast a value as a certain type CONVERT() Cast a value as a certain type Cast functions and operators enable conversion of values ...
https://dev.mysql.com/doc/refman/8.4/en/constant-folding-optimization.html
Comparisons between constants and column values in which the constant value is out of range or of the wrong type with respect to the column type are now handled once during query optimization rather row-by-row than during execution. The comparisons ...
https://dev.mysql.com/doc/refman/8.4/en/cost-model.html
To generate execution plans, the optimizer uses a cost model that is based on estimates of the cost of various operations that occur during query execution. The optimizer has a set of compiled-in default “cost constants” available to it to make ...
https://dev.mysql.com/doc/refman/8.4/en/create-table-generated-columns.html
Values of a generated column are computed from an expression included in the column definition. Generated column definitions have this syntax: col_name data_type [GENERATED ALWAYS] AS (expr) [VIRTUAL | STORED] [NOT NULL | NULL] [UNIQUE [KEY]] ...
https://dev.mysql.com/doc/refman/8.4/en/example-auto-increment.html
You can also explicitly assign 0 to the column to generate sequence numbers, unless the NO_AUTO_VALUE_ON_ZERO SQL mode is enabled. For example: INSERT INTO animals (id,name) VALUES(0,'groundhog'); If the column is declared NOT NULL, it is also ...
https://dev.mysql.com/doc/refman/8.4/en/information-schema-innodb-trx-table.html
The INNODB_TRX table provides information about every transaction currently executing inside InnoDB, including whether the transaction is waiting for a lock, when the transaction started, and the SQL statement the transaction is executing, if any.
https://dev.mysql.com/doc/refman/8.4/en/information-schema-partitions-table.html
Each row in this table corresponds to an individual partition or subpartition of a partitioned table. The PARTITIONS table has these columns: TABLE_CATALOG The name of the catalog to which the table belongs. TABLE_SCHEMA The name of the schema ...
https://dev.mysql.com/doc/refman/8.4/en/invisible-columns.html
An invisible column is normally hidden to queries, but can be accessed if explicitly referenced. As an illustration of when invisible columns may be useful, suppose that an application uses SELECT * queries to access a table, and must continue to ...
https://dev.mysql.com/doc/refman/8.4/en/performance-schema-events-transactions-current-table.html
The table stores one row per thread showing the current status of the thread's most recent monitored transaction event, so there is no system variable for configuring the table size. For example: mysql> SELECT * FROM ...