Hello everyone, I have a challenge to; sum all values in one column in list A, when another column in this list meets certain criteria, then save that sum to list B against a matching Title field. also to recalculate the sum when new items are added to list A (rather than just add the new value as the criteria might have changed)
If a sum hasn't been made before it will make a new item in List B with the same title as the title in list A. if there is an item in list B that has a matching title it will update the sum field rather than create another item.
So in List A there may be hundreds of items with the same title, but in List B there will be one item per unique title which sums all of List A's value columns.
My first thought was a workflow but i cannot find away to sum all items let alone then add criteria to the sum.
Has anyone got any ideas how i can do this? Any help would be much appreciated.