DELIVERY is a Table is where I store when a customer purchases a product.
Among others there are 4 key fields:
1- PURCHASE_DATE (my entry stored field)
2- EXPIRE_DATE (stored calculation).
3- PREVIOUS_EXPIRE_DATE (unstored calculation) obtained using a relationship which shows the EXPIRE_DATE of previous record (based on date)
The relationship called previous_record" works fine and is based on Name=Name, RecordID≠RecordID, Date>Date
4- DELAY (unstored calculation) = PURCHASE_DATE - PREVIOUS_EXPIRE_DATE.
All fine except that, since PREVIOUS_EXPIRE_DATE in unstored, also DELAY is unstored.
When producing report using a portal, with some 150.000 records, the time for obtaining the result is frustrating.
I wish to have a PREVIOUS_EXPIRE_DATE stored with a lookup so that DELAY refers to it.