Re: R: Help lock record

On 24-May-06, at 1:12 AM, bitrunner wrote:

>
> On 23-May-06, at 1:37 PM, bitrunner wrote:
>
> > For lock the record I use:
> > select * from orders where id = 17 for update
> >
> > in this way lock the record with id = 17.
> > If an other user demands the same record as I can understand that
> it is lock?
>
> > yes as long as autocommit is false this is true. In other words as
> > long as you do this inside a transaction/
>
>
> sorry but I dont have to understand.
> How I can understand that there is an other user who lock the record?

I think I understand the question. You want to know how to determine
if the record is locked.

As far as I know there isn't a way. If process A locks the record,
then process B attempts to lock the record it will block until
process A releases the record.

If you have statement_timeout set to some value other than -1 then
process B will timeout after waiting for the statement_timeout.
Otherwise it will block until process A is finished with the record.

Dave
>
> Thanks.
>
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