Report data flow

One of the principal advantages of the NAV report is its built-in data flow structure. At the beginning of any report, we define DataItems (the tables) that the report will process. We can create a processing-only report that has no data items (if no looping-through database data is required), but this situation often calls for a code unit to be used. In a report, NAV automatically creates a data flow process for each DataItem, or table reference. This automatically created data flow provides specific triggers and processing events for each data item:

• Preceding DataItem
• After reading each record of DataItem
• Following the end of DataItem

The underlying "black-box" report logic (the part that we can't see or affect) automatically loops through the named tables, reading and processing one record at a time. Therefore, any time, we need a process that steps through a set of data one record at a time, it is often easier to use a report object.

The reference to a database...