Re: Autogenerated Sequence

[Muhammad Aamir <ma...@aamir.pk>]

Please validate my conclustion:

   - I will create a record in *SequenceValueItem* table with seqName
   'mrNbr' for example.

   - When I create new patient, in the same service I will get seqId and
   will put this value as patientNbr (or mrNbr) in my table and will add 1 in
   seqId.

   - I will update *SequenceValueItem *and my table (patient records) and in
   the same time if someone else is trying to update *SequenceValueItem *table
   with the same seqId, it will through an exception because of pessimistic
   locking.

Thank you
Muhammad Aamir

On Sat, Apr 25, 2009 at 3:52 AM, BJ Freeman <bj...@free-man.net> wrote:

> So is there any thoughts against adding a parm to enforce the sequential
> numbering where it will not jump numbers?
>
> David E Jones sent the following on 4/24/2009 3:16 AM:
> >
> > The problem is that this code is meant for performance and throws away
> > sequence values all the time. For example, it gets banks of 10 numbers
> > at a time and if not used are thrown away. Also, this runs in a separate
> > transaction to be non-blocking and has collision detection to avoid
> > mishaps, and if a collision is detected then the whole bank attempted
> > will be thrown away.
> >
> > -David
> >
> >
> > On Apr 23, 2009, at 9:41 PM, BJ Freeman wrote:
> >
> >> My understanding was that he wanted to have an Id for medical records
> >> since nothing else would use that sequence name it would be sequencel
> >> staggerMax is set to 1 by default
> >>  public String getNextSeqId(String seqName) {
> >>        return this.getNextSeqId(seqName, 1);
> >>    }
> >> now if you call
> >> public String getNextSeqId(String seqName, long staggerMax) {
> >>        Long nextSeqLong = this.getNextSeqIdLong(seqName, staggerMax);
> >>
> >>        if (nextSeqLong == null) {
> >>            // NOTE: the getNextSeqIdLong method SHOULD throw a runtime
> >> exception when no sequence value is found, which means we should never
> >> see it get here
> >>            throw new IllegalArgumentException("Could not get next
> >> sequenced ID for sequence name: " + seqName);
> >>        }
> >>
> >>        if
> >> (UtilValidate.isNotEmpty(this.getDelegatorInfo().sequencedIdPrefix)) {
> >>            return this.getDelegatorInfo().sequencedIdPrefix +
> >> nextSeqLong.toString();
> >>        } else {
> >>            return nextSeqLong.toString();
> >>        }
> >>    }
> >>
> >> then it would be staggered. this is not defualt
> >>
> >> or have I missed something.
> >>
> >>
> >> David E Jones sent the following on 4/23/2009 8:21 PM:
> >>>
> >>> When you look at the code you'll find it most certainly will skip, in
> >>> fact the default sequencing is designed for skipping to be okay in
> order
> >>> to perform better.
> >>>
> >>> If you want a more strict sequence then take a look at the invoiceId
> >>> generation in the createInvoice service. It is configurable and some of
> >>> the options are meant to make things sequential. Be aware though that
> >>> because of the way transactions work by default (ie the transaction
> >>> isolation done), depending on the transaction isolation it can be
> >>> possible for skips to happen (ie because of phantom reads, etc), it's
> >>> just not as likely.
> >>>
> >>> -David
> >>>
> >>>
> >>> On Apr 23, 2009, at 6:16 PM, BJ Freeman wrote:
> >>>
> >>>> suggest you look at the code to make you confident.
> >>>>
> >>>> Muhammad Aamir sent the following on 4/23/2009 5:06 PM:
> >>>>> And sure it will never skip (as well as repeate)?
> >>>>>
> >>>>> Thanks
> >>>>>
> >>>>> On Fri, Apr 24, 2009 at 2:34 AM, BJ Freeman <bj...@free-man.net>
> >>>>> wrote:
> >>>>>
> >>>>>> look at the
> >>>>>>
> >>>>>>
> https://demo.ofbiz.org/webtools/control/FindGeneric?entityName=SequenceValueItem&find=true&VIEW_SIZE=50&VIEW_INDEX=0
> >>>>>>
> >>>>>>
> >>>>>> you can define your own sequence name
> >>>>>>
> >>>>>> delegator.getNextSeqId uses this
> >>>>>>
> >>>>>>
> >>>>>> Muhammad Aamir sent the following on 4/23/2009 4:18 PM:
> >>>>>>> I am working on an Outpatient Management module for a clinic.
> >>>>>>> I've to
> >>>>>> extend
> >>>>>>> Person entity adding mrNbr (medical record number) field. The field
> >>>>>> should
> >>>>>>> keep incremented automatically and must not repeat and preferably
> >>>>>>> not
> >>>>>> skip
> >>>>>>> as well.
> >>>>>>>
> >>>>>>> Can anybody give me a clue on it (I tried in documentation pages
> but
> >>>>>> didn't
> >>>>>>> get any hint).
> >>>>>>>
> >>>>>>> Also, is there any page where all entity field data types of ofbiz
> >>>>>>> entity
> >>>>>>> engine are explained?
> >>>>>>>
> >>>>>>> Thanks
> >>>>>>> Muhammad Aamir
> >>>>>>>
> >>>>>>
> >>>>>
> >>>>
> >>>
> >>>
> >>
> >> --
> >> BJ Freeman
> >> http://www.businessesnetwork.com/automation
> >> http://bjfreeman.elance.com
> >> Systems Integrator.
> >>
> >
> >
>
> --
> BJ Freeman
> http://www.businessesnetwork.com/automation
> http://bjfreeman.elance.com
>
> http://www.linkedin.com/profile?viewProfile=&key=1237480&locale=en_US&trk=tab_pro
> Systems Integrator.
>
>