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, 200718 yr by Guest

Set the field to unique value?

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