Serialnumber duplicates

[m.versteegh]

I have developed a database in which the company enters all incoming and outgoing post. The problem is when two or more users enters a new postpiece at the same time (two are more users are entering a new record at the same time). The calculated serial number will be the same for users that are inserting a new record at the same time. I know the problem has to do with the used calculation, but I don't have a clue how to solve it. The database is added as attachment.

versie6a.fp7.zip

Edited November 22, 2007 by Guest

[Anuviel]

Set the field to unique value?

[LaRetta]

Hi m.versteegh, welcome to FM Forums

There is no way to guarantee that you will not have duplicates unless you let FileMaker itself generate the auto-enter serial (that's what it is for). Otherwise, when used in a multi-user environment, there is always possibility of duplicates because:

1) User A creates a new record

2) Serial Number 44 is assigned

3) User A leaves cursor in field

4) User B creates a new record

5) FileMaker has NO WAY of knowing that User A has used serial 44 until User A leaves (commits) the record.

6) FileMaker assigns User B's record, serial number 44.

I highly suggest dropping the idea of using a calculation and let FileMaker generate one properly.

LaRetta