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Okay. So this is what I've done as you see,

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it looks a little nicer than it was before. And I didn't

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really change that much. I just made a few changes, so

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I just wanted to point them out to you, so that you

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know what they are. And the main thing, one of the

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main things I did is really to introduce these derived attributes. So

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these are attributes that are basically

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computed. Based on some other attributes.

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Okay, they don't have a value themselves, but their value is computed.

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And I used two. The first one is age. So

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basically we know the age of the patron based on

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the birthday, of the patron. So you guys, I don't

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know if you have that information currently in the system.

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>> No, we'll have to add that to the

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form patrons fill out, when they get their card.

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>> Is that, that an issue? Can you do it?

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>> No yes, we, we can easily do that.

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>> Okay, so then, perfect. So we'll do it that way. I think it's

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a, in a little cleaner. And similarly, since you told me that the fine

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was computed based on the amount of days that an

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item was late. The patron was late returning the item, then I

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also added this as a derived attribute that is computed based on

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the due date and when the item is actually returned.

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>> Makes sense.

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>> Makes sense? Okay. And the rest

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is kind of really minor things. So the, the only one I

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want to point out is I didn't, you know, discuss that with

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you before, but I added this, which is called cardinality

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for some of these relationships. And what they say is basically

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is how many elements are involved in the relationship.

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>> So, you mean the stars?

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>> Yeah, like the stars and the one...

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>> Okay.

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>> Here for example, this is telling you that for each item there

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is only one title. And that for each title, there are multiple items.

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>> So, star means many.

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>> Stars mean many, yeah.

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>> Okay, go you.

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>> Sorry that's kind of computer science lingo - we use the star

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for that kind of stuff. And, similarly, for the patron, it's

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telling me that, you know, each patron can have multiple, can

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request multiple titles, and that the same title can be requested

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by multiple patrons, which I think is the way the system works.

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>> Right. So except for these minor changes,

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we already had a pretty good model in our hands, so

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I think is a, we can finalize this and then just

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move to the low level design and then implementation, and be

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done with the system.

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>> Sounds good.