有没有最好的方法来避免在 Oracle 中多次执行进程?
假设我有一个名为 myproc 的 procedure.这是一个复杂的过程，我不能允许两个实例同时执行 proc.
Let's say that I have a procedure called myproc. This is a complex process and i cannot allow two instances executing at the same time the proc.
实际上我使用dbms_application_info.set_module来做到这一点:
Actually I do this using the dbms_application_info.set_module:
procedure start_process is
begin
dbms_application_info.set_module('myproc', 'running');
end;
并在运行该过程之前进行验证:
and verify before run the process:
select 'S'
from v$session v
where v.module = 'myproc'
and v.action = 'running';
在数据库层面，有没有更好的方法来检查这个?
In the database level, is there a better way to check this?
推荐答案
使用 dbms_lock.allocate_unique 以及 dbms_lock.request.使用说明说:
使用新锁名称调用 ALLOCATE_UNIQUE 的第一个会话导致要生成并存储在 dbms_lock_allocated 表中的唯一锁 ID.后续调用(通常由其他会话)返回先前生成的锁 ID.
The first session to call ALLOCATE_UNIQUE with a new lock name causes a unique lock ID to be generated and stored in the dbms_lock_allocated table. Subsequent calls (usually by other sessions) return the lock ID previously generated.
我认为这可能就是您所追求的.
I think this could be what you're after.
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