I have a nested form called costing which has the prices and who the price is assigned to (vendor, Ikon, Miscellaneous) i also have 3 seperate fields called vendor total, ikon total and miscellaneous total, in which i want the sum of line total against each cost head.
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Are these SUM or TOTAL columns real columns ?
if so you could use reference actions. The sample app below shows updates from parent to child. You could use a reverse flow.