Subtotal on field

[batguano]

How do I do a subtotal on a group of related items. For example, if I have a field called ItemNo that has an amount field for that record and I want to subtotal the amount for that item number, how do I do this?

[LiveOak]

If your primary database is DB1 and the related file is DB2 and they are related by Item No.using a relationship called RelItem, Create an "Item Total" field in DB1 defined as Sum(RelItem::Amount). For a record in DB1 this will total the Amount field for only the related records in DB2.