Mysql：函数之二： miscellaneous functions

 

Miscellaneous Functions

Name	Description
DEFAULT()	Return the default value for a table column
GET_LOCK()	Get a named lock
INET_ATON()	Return the numeric value of an IP address
INET_NTOA()	Return the IP address from a numeric value
IS_FREE_LOCK()	Checks whether the named lock is free
IS_USED_LOCK()(v4.1.0)	Checks whether the named lock is in use. Return connection identifier if true.
MASTER_POS_WAIT()	Block until the slave has read and applied all updates up to the specified position
NAME_CONST()(v5.0.12)	Causes the column to have the given name
RAND()	Return a random floating-point value
RELEASE_LOCK()	Releases the named lock
SLEEP()(v5.0.12)	Sleep for a number of seconds
UUID_SHORT()(v5.1.20)	Return an integer-valued universal identifier
UUID()(v4.1.2)	Return a Universal Unique Identifier (UUID)
VALUES()(v4.1.1)	Defines the values to be used during an INSERT