Re: Locking issues

From: Steve Cosner <stevec_at_zimmer.csufresno.edu>
Date: 1997/02/15
Message-ID: <5e3lta$s9e@shadow.CSUFresno.EDU>#1/1

It is difficult to write C/S applications with Oracle's default locking. I have spent many hours programming and testing processes to handle locked rows gracefully. (Sometimes you just can't use Forms default processing.)

It seems like Oracle could change the necessity of having to do a "select for update nowait" by providing a parameter on the Update command, maybe something like "wait limit=5 seconds", and returning an error if the row remains locked for the entire wait period.

It would also help on-line processing environments if there were a system-level method of rolling-back any session/transaction where a lock is being held over 5 minutes with no further activity in the session. There needs to be a method of clearing out locks held by a terminal operator who has locked something and then answered the phone or gone to lunch, or even worse, shut down the client terminal without exiting the process.

Once a client terminal has been shut down without, committing, or rolling-back, there is nothing that will clear the problem without intervention by the DBA.

If I am wrong about this, please let me know. If I'm right, I sure hope Oracle will work on a solution.

Steve Cosner

---

Free forms software at
http://members.aol.com/stevec5088

In article <3304b9d3.20626929_at_nntp.mediasoft.net>, Thomas J. Kyte <tkyte_at_us.oracle.com> wrote:
>the way Oracle Forms handles this is as follows:
>
>1) query up the information, include the rowid for each table in the query.
>
>2) when a user attempts to modify a value (before they actually modify it), the
>applications issues:

 <snip>
>
>
>
>
>On 14 Feb 1997 16:43:10 GMT, "David Kaiser" <davidk_at_sfmic.com> wrote:
>
>>Oracle's default locking method causes C/S applications to wait for a lock
>>to clear. This can make the user think that their program crashed, when
>>they are actually waiting for a lock.
>>
>>The only way around this that I've seen is to have the client program
>>timeout after waiting for a certain period of time.
>>
>>Is there anyway with Oracle 7.3 to have Oracle return an error message
>>notifying the client program that the record it is trying to update is
>>locked?
  Received on Sat Feb 15 1997 - 00:00:00 CST