Re: Autogenerated Sequence

[BJ Freeman]

Refer to org.ofbiz.entity.util.SequenceUtil
I am looking at this in hopes of commig up with solution
however there is another email between Japco and david that goes into
this further.
I am redirecting this to the dev list and will bump up the other email
so you can read it.

Muhammad Aamir sent the following on 5/1/2009 12:26 AM:

> 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 <[hidden email]> 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 <[hidden email]>
>>>>>>> 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.
>>
>>
>

--
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.