-Okay. So this is what I've done as you see, - -2
-it looks a little nicer than it was before. And I didn't - -3
-really change that much. I just made a few changes, so - -4
-I just wanted to point them out to you, so that you - -5
-know what they are. And the main thing, one of the - -6
-main things I did is really to introduce these derived attributes. So - -7
-these are attributes that are basically - -8
-computed. Based on some other attributes. - -9
-Okay, they don't have a value themselves, but their value is computed. - -10
-And I used two. The first one is age. So - -11
-basically we know the age of the patron based on - -12
-the birthday, of the patron. So you guys, I don't - -13
-know if you have that information currently in the system. - -14
->> No, we'll have to add that to the - -15
-form patrons fill out, when they get their card. - -16
->> Is that, that an issue? Can you do it? - -17
->> No yes, we, we can easily do that. - -18
->> Okay, so then, perfect. So we'll do it that way. I think it's - -19
-a, in a little cleaner. And similarly, since you told me that the fine - -20
-was computed based on the amount of days that an - -21
-item was late. The patron was late returning the item, then I - -22
-also added this as a derived attribute that is computed based on - -23
-the due date and when the item is actually returned. - -24
->> Makes sense. - -25
->> Makes sense? Okay. And the rest - -26
-is kind of really minor things. So the, the only one I - -27
-want to point out is I didn't, you know, discuss that with - -28
-you before, but I added this, which is called cardinality - -29
-for some of these relationships. And what they say is basically - -30
-is how many elements are involved in the relationship. - -31
->> So, you mean the stars? - -32
->> Yeah, like the stars and the one... - -33
->> Okay. - -34
->> Here for example, this is telling you that for each item there - -35
-is only one title. And that for each title, there are multiple items. - -36
->> So, star means many. - -37
->> Stars mean many, yeah. - -38
->> Okay, go you. - -39
->> Sorry that's kind of computer science lingo - we use the star - -40
-for that kind of stuff. And, similarly, for the patron, it's - -41
-telling me that, you know, each patron can have multiple, can - -42
-request multiple titles, and that the same title can be requested - -43
-by multiple patrons, which I think is the way the system works. - -44
->> Right. So except for these minor changes, - -45
-we already had a pretty good model in our hands, so - -46
-I think is a, we can finalize this and then just - -47
-move to the low level design and then implementation, and be - -48
-done with the system. - -49
->> Sounds good. - -- cgit 1.4.1