1945.3.5
by Marisa Plumb
more sql doc modifications |
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User Defined Locks
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1933.1.9
by Brian Aker
Additional documentation and testing. |
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A user can create a "lock" which is scoped to their user space. Multiple |
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session of the user can see the lock. |
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SELECT GET_LOCK(); |
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SELECT GET_LOCKS(); |
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SELECT RELEASE_LOCK(); |
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SELECT RELEASE_LOCK(); |
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SELECT RELEASE_LOCKS(); |
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SELECT is_free_lock(); |
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SELECT is_used_lock(); |
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1955.1.1
by Brian Aker
Finally added pieces so that you can do a drop lock and wait. |
21 |
SELECT wait_for_lock(); |
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SELECT release_lock_and_wait(); |
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1945.3.5
by Marisa Plumb
more sql doc modifications |
25 |
If a session should exit, whatever locks it was holding will be deleted. |
1933.1.9
by Brian Aker
Additional documentation and testing. |
26 |
|
1945.3.5
by Marisa Plumb
more sql doc modifications |
27 |
Please note, get_lock() was designed to be compatible with MySQL. If you |
1933.1.9
by Brian Aker
Additional documentation and testing. |
28 |
hold any locks when calling get_lock() they will be released. For this |
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reason you may want to consider calling get_locks() instead. |
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1955.1.1
by Brian Aker
Finally added pieces so that you can do a drop lock and wait. |
31 |
release_lock_and_wait() released the named lock, and then waits for another |
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session to try to obtain ownership. If it does not own the lock, it returns |
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with a zero. |
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1933.1.9
by Brian Aker
Additional documentation and testing. |
35 |
Information on all barriers can be found in the DATA_DICTIONARY.USER_LOCKS |
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table; |