Re: Executing UNIX commands from Oracle

In article <Thomas.B.Cox.28.2F4E4DCB_at_tek.com> Thomas.B.Cox_at_tek.com (Thomas B Cox) writes:
>>>[...] can i [...] have a stored procedure actually execute
>>>operating system commands?
 

>>You could not do this directly, as far as I know. The only thing I can think
>>of is to use the ORACLE database pipe packaged procedures to set up
>>a client-server type arrangement. I haven't got the manuals to hand but the
>>concept is that :-
 

>> 1) A server process (implemented in Pro*C for example) listens on a pipe
>> 2) your stored procedure passes the script details down the pipe
>> 3) the server uses the system() call to execute the script
>
>Step 1 is not as easy as it looks. I recommend using the DBMS_ALERT package.
>(Otherwise you're running a resource-intensive loop of constantly trying to
>grab stuff out of the pipe even when it's empty, which may be most of the
>time.)

The program on the listening end of either the DBMS_PIPE or DBMS_ALERT is blocked waiting for input - no busy loop is required either way.

The difference between the pipe and the alert is that the alert is transaction oriented and won't happen if the transaction doesn't complete.

Joe

-- 
Joe Halpin 
jhalpin_at_netcom.com 
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