>>>>>Actually, then I heard from someone, in a discussion on the subject, that the most complicated and largest contraption in use, an ocean liner, didn't go deeper than ten levels.
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>>>>Last statement is interesting. Of course, once you go beyond one level the only approach that makes sense is a self-referencing/recursive one.
>>>>
>>>>The one I worked on was basically for recipes (i.e. food). There were ~1000 ingredients from which recipes were built. More than five levels were quite common. Also fractions of a recipe as well as multiples were allowed. e.g based on Bread:
>>>
>>>Amazing... same happened to me. I ported that assembly line app to serve a restaurant :). The same principle, with proportional costing if a subrecipe was included in quantity different from 1 - if, say, a standard salad was served on the main dish, it would go as half, whereas as a whole if served as a side dish, etc.
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>>I guess this particular wheel has been re-invented a lot - swap the terminolgy a bit (portion, meal, recipe, component, pack etc) but the underlying logic is the same. In the one I worked on the basic ingredients had over 60 fields quantifying not only carbohydrate, protein etc but also vitamin and trace element content so that nutritional values for final products could be calculated. Used by restaurants, food producers, hospitals etc....
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>>>As a curiosity, I also had to write the bar side of the restaurant app, with daily inventory by the bottle and how much should remain in a started bottle. If one bottle of vinjak (Yugoslav variant of cognac) holds 1l, that is 20 shots per 0,05 l - so if they served 12, there should be 0,4l left in the bottle. Goes (somewhere) to show how much the owner trusted his waiters :).
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>>I've yet to meet a bar owner who admits to *any* trust in bartenders. I once spent an idle hour at Kennedy during which the bartender explained to me the numerous scams that were rife in the trade.....
>
>Exactly. It's a fact of life in that business. As long as the bartender doesn't go overboard, it's just part of your costs. Even with the "shrinkage" owners make a fortune through the bar. Liquor and soft drinks are the highest margin items in the place. When customers are paying $6 or 7 for a glass of mundane wine, that much or more for an ounce of alcohol and a mixer, you're a happy owner.

I was told a favourite scam for a bartender was simply to bring in their own bottles. At the end of the day the stock and the till tallied perfectly - but, for example, 10 bottles of whisky rather than 8 had actually been sold.