Re: Restrict Access

[Paul DuBois]

At 9:23 PM +0200 7/27/99, Martin Ramsch wrote:
>On Di, 1999-07-27 14:03:19 -0500, Paul DuBois wrote:
>> I have a fairly basic question about GET_LOCK():  what is it that's
>> being locked?
>
>Any further call to GET_LOCK() using the same lock name.
>It will block until the first (successful one) is released again.

I tried the following and both calls returned successfully, and
immediately:

mysql> SELECT GET_LOCK("a",10);
+------------------+
| GET_LOCK("a",10) |
+------------------+
|                1 |
+------------------+
1 row in set (0.00 sec)

mysql> SELECT GET_LOCK("a",10);
+------------------+
| GET_LOCK("a",10) |
+------------------+
|                1 |
+------------------+
1 row in set (0.00 sec)


If GET_LOCK() is called in two different threads with the same lock
name, then the second one blocks.  I take it, then, that GET_LOCK()
provides cooperative locking only?

-- 
Paul DuBois, paul@stripped