Multi-tenant Question

weblike

Hi,

I have created an Invoice system. All is good until more users create an invoice in the same time.

I have an BO which holds the series of the invoices. Inside this BO I have BOSerie.CurrentNumber which is the current number of the serie and is increased each time e new invoice is created by a process.

The process does like this:

ENTER NEW Invoice
Increase BOSeries.CurrentNumber By 1

If 2 users fires up this process in the same time they ends up with the same number for that invoice.

I cannot increase the current number before ENTER NEW, because it happens that users change their mind and cancel the creating process. If that happens in the system I will have empty invoices..Not good.

I know if I scratch my brains harder I will find the solution , but it's more easier to cry for help hoping someone invented the wheel already 🙂

Thank you.

tford

To deal with this situation:

I cannot increase the current number before ENTER NEW, because it happens that users change their mind and cancel the creating process. If that happens in the system I will have empty invoices..Not good.

you could have another flag after the ENTER NEW is completed that indicates that the invoice is "real" and the invoice number was used. The invoices without this 2nd flag turned on become unused or void invoice numbers which have been accounted for.

weblike

Thank you Tom,

Very simple and logic.

Nice day,

ACDC

For Invoice numbers or any sequential number if you use MAX it should take care of the number position if the Invoice was never created,.
e.g: Invoice.Number=MAX Invoice.Number+1

BenHayat

ACDC wrote
For Invoice numbers or any sequential number if you use MAX it should take care of the number position if the Invoice was never created,.
e.g: Invoice.Number=MAX Invoice.Number+1

That's what I use for any sequential numbers.

rocketman

I tend to put an sequential number attributes in SystemSettings so they are always available to the app. Then I put the increment code (INCREASE or MAX) in a rule in the BO (instead of in the process) . That way if a user cancels an input for whatever reason the number will not get incremented. Further - if there are two people inputting invoices, they will never get the same number because the rule engine will serve the numbers on a first come first serve basis.

The Rule would look something like (IF BO IS NEW and BO.InvoiceNumber IS UNDEFINED THEN BO.InvoiceNumber=SystemSetting.NextInvoiceNumber

INCREASE SystemSettings.NextInvoiceNumber BY 1

** Note - DO NOT run this at form initialisation time - let the rule engine do its job and decide when to fire the rule. The combination of IS NEW and UNDEFINED will ensure you don't get a double bounce on the numbers since it will stop the rule engine firing twice