https://dev.mysql.com/innodb-online-ddl-failure-conditions.html
For example, you might insert duplicate values into a column while a unique index is being created, or you might insert NULL values into a column while creating a primary key index on that column. The failure of an online DDL operation is typically ...
https://dev.mysql.com/innodb-undo-tablespaces.html
Unique undo tablespace file names are recommended to avoid potential file name conflicts when moving or cloning data. Undo tablespaces contain undo logs, which are collections of undo log records that contain information about how to undo the ...
https://dev.mysql.com/insert-select.html
To avoid ambiguous column reference problems when the SELECT and the INSERT refer to the same table, provide a unique alias for each table used in the SELECT part, and qualify column names in that part with the appropriate alias. INSERT ...
https://dev.mysql.com/installing-source-distribution.html
The first strategy places all build directories at the same level, which requires that you choose a unique name for each. To install MySQL from a standard source distribution: Verify that your system satisfies the tool requirements listed at ...
https://dev.mysql.com/json.html
JSON_MERGE_PRESERVE() handles multiple objects having the same key by combining all unique values for that key in an array; this array is then used as the value for that key in the result. The JSON data type provides these advantages over storing ...
https://dev.mysql.com/key-column-usage-table.html
One row with CONSTRAINT_NAME = 'CO', TABLE_NAME = 't3', COLUMN_NAME = 's2', ORDINAL_POSITION = 1, POSITION_IN_UNIQUE_CONSTRAINT = 1. This table provides no information about functional key parts because they are expressions and the table provides ...
https://dev.mysql.com/keyring-okv-plugin.html
Note The keyring_okv plugin is an extension included in MySQL Enterprise Edition, a commercial product. The Key Management Interoperability Protocol (KMIP) enables communication of cryptographic keys between a key management server and its clients.
https://dev.mysql.com/keywords.html
Certain keywords, such as SELECT, DELETE, or BIGINT, are reserved and require special treatment for use as identifiers such as table and column names. This may also be true for the names of built-in functions. Reserved words are permitted as ...
https://dev.mysql.com/ldml-collation-example.html
To add a UCA collation for a Unicode character set without recompiling MySQL, use the following procedure. If you are unfamiliar with the LDML rules used to describe the collation's sort characteristics, see Section 10.14.4.2, “LDML Syntax ...
https://dev.mysql.com/locking-functions.html
Uniquely named locks acquired with GET_LOCK() appear in the Performance Schema metadata_locks table. While held by one session, other sessions cannot obtain a lock of the same name. Returns 1 if the lock was obtained successfully, 0 if the attempt ...
