On a simple invoice DB I built, while adding line items, how can I automatically increase the quantity of the product for products that have already been added.. Rather than having duplicate items occupy the invoice...  Items are added via script... Thanks 

Script trigger can handle it nicely (please see attached).  Overview:

• Script trigger attached to LineItem Quantity field OnObjectExit tests if there same product is on same invoice
• If so, entered quantity is added to the 'other' duplicate (see relational graph for filtered join).
• Then the current portal row is deleted.

An added benefit of deleting the record is that, if one uses Revert Record/Request at this point, other changes in the parent could be lost as well.  In addition, if one reverts the current new record in the portal, FM refuses to set the related quantity and still allow reversion of the 'parent' line item. 

CombineLines.fmp12.zip

Edited October 23, 201510 yr by LaRetta

Thanks for your reply... I am very grateful