From what I can see it seems to show that IF the ITEM TAG:Warehouse value is Not null, then ITEM TAG:Warehouse is to be added to a ticket.
But after going through that tutorial it explains, the action is created so that::
Therefore that rule that you posted indicates
When a new order is added, and IF a warehouse is assigned to product, that action will update the specific order’s warehouse in entity screen so it shows(Example) [quote=“emre, post:1, topic:8121”]
and 150 GR meat consumed from Pakistani Kitchen.
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It’s just used if you have more than one type of kitchen. If this is your setup also, the rule is made so it updates the warehouse item consumption appropriately according to item which is assigned to a specific kitchen.
E.g If chinese food kitchen is selected and an item is ordered, then under warehouse, Chinese Kitchen entity will show for that particular order this amount of meat or product was used.
I don’t know if this is the answer you’re looking for, but from what I gathered from that rule and tutorial, the rule just ensures that based on what kitchen is selected, it would update that kitchen consumption accordingly using that rule.