Automation: Trigger on Summary Field Change

Hi Mark. Thank you for the quick response. Here is an overview of the problem, in detail. I have two tables, one for Purchase Orders, and one for Line Items. The Line Items are parts which are ordered. There is a checkbox on the Line Items record which denotes when the part is received. The Purchase Order record has two summary fields; one totaling Parts Outstanding, and one totaling Parts Received, derived from that checkbox. I am trying to create an automation that automatically changes the PO status to closed when Parts Outstanding =0 and Parts Received is >0. 

My only concern with the solution you noted above is that the data may change multiple times, as parts are not received all at once, so it may not always accurately reflect the Parts Outstanding =0.

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Matthew Witzgall
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