Oracle 5.0 Reference Manual page 987

of log events the slave had to wait for to advance to the specified position. The function returns
if the slave SQL thread is not started, the slave's master information is not initialized, the arguments
are incorrect, or an error occurs. It returns
thread stops while
MASTER_POS_WAIT()
past the specified position, the function returns immediately.
If a value is specified,
timeout
seconds have elapsed.
timeout.
•
NAME_CONST(name,value)
Returns the given value. When used to produce a result set column,
the column to have the given name. The arguments should be constants.
mysql> SELECT NAME_CONST('myname', 14);
+--------+
| myname |
+--------+
| 14 |
+--------+
This function was added in MySQL 5.0.12. It is for internal use only. The server uses it when writing
statements from stored programs that contain references to local program variables, as described
in Section 18.6, "Binary Logging of Stored
mysqlbinlog.
•
RELEASE_LOCK(str)
Releases the lock named by the string
if the lock was released,
released), and
NULL
by a call to
GET_LOCK()
The statement is convenient to use with
DO
Syntax".
•
SLEEP(duration)
Sleeps (pauses) for the number of seconds given by the
[967] is interrupted, it returns 1. The duration may have a fractional part. This function
SLEEP()
was added in MySQL 5.0.12.
• [967]
UUID()
Returns a Universal Unique Identifier (UUID) generated according to "DCE 1.1: Remote Procedure
Call" (Appendix A) CAE (Common Applications Environment) Specifications published by The Open
Group in October 1997 (Document Number C706,
c706.htm).
A UUID is designed as a number that is globally unique in space and time. Two calls to
[967] are expected to generate two different values, even if these calls are performed on
UUID()
two separate computers that are not connected to each other.
A UUID is a 128-bit number represented by a
aaaaaaaa-bbbb-cccc-dddd-eeeeeeeeeeee
• The first three numbers are generated from a timestamp.
• The fourth number preserves temporal uniqueness in case the timestamp value loses monotonicity
(for example, due to daylight saving time).
Miscellaneous Functions
-1
[966]
MASTER_POS_WAIT()
must be greater than 0; a zero or negative
timeout
[967]
Programs", You might see this function in the output from
[967]
that was obtained with
str
if the lock was not established by this thread (in which case the lock is not
0
if the named lock did not exist. The lock does not exist if it was never obtained
[965] or if it has previously been released.
RELEASE_LOCK()
[967]
967
if the timeout has been exceeded. If the slave SQL
is waiting, the function returns NULL. If the slave is
[966] stops waiting when
NAME_CONST()
GET_LOCK()
[967]. See
argument, then returns 0. If
duration
http://www.opengroup.org/public/pubs/catalog/
string of five hexadecimal numbers in
utf8
format:
NULL
timeout
means no
timeout
[967] causes
[965]. Returns
1
Section 13.2.3, "DO