 So, to continue to expand on this idea, we're going to just continue to make other things. Well, any invoice actually kind of has a reference to any visit, if we remember that was kind of something I had said earlier. So I actually want my visit ID, my visit ID from my visit table, that guy right there. I want that to also appear inside of my invoice because, again, I need to reference it in some different way. We're going to keep it as a short text this time, but instead of this being considered my primary key, when we start to build our relationships of our database, this is actually considered something called a foreign key. And that foreign key is just saying that this is a unique identifier to another table. And I typically like to at least specify what my table is that I'm working with. I want to go down here to my properties section. You notice how for both of my invoice num in my visit ID, as I look at them, they both have pretty much the same properties. Well, let's say, for example, for invoice ID, I want to click on that. You see that it says down here field size 255. Well, what does that mean? Well, what that means is how many alpha numeric characters, letters, numbers, symbols I can have appear in this field, 255. It's a little big for what we need. If you think about our student ID numbers, those are only seven digits long. We seem to be doing just fine. Since we're dealing with an urgent care place, I don't expect them to be booming with business. There's tons of them. We're going to actually change this to just five. Now again, what this does is it says, it limits it to say only five alpha numeric characters can come in. We're going to keep on going and I'm going to actually say we also want to change my caption. Again, if we look at my field name, it's invoice num and there's no spacing and it's all one word. Well, again, that's good for the IT guy. It's good for the IT guy because once upon a time, databases couldn't handle spaces. It's just kind of a thing that we still do today just as a convention, but I'm not IT guy. I'm normal person who has to do this for homework assignment. What we can do is we can come in here and say invoice, invoice space number. That's perfectly fine. What will happen is this will actually be what we see in just a little bit. Just to continue expanding on this, now, visit ID. Well, visit ID, if we look at the visit table again, there are only four characters. Every one of my visits is only four characters long, so I don't need to make this five, but I do want it to be four. The same idea comes in here is that if we think about it, I don't want to give a visit ID. I don't want to type in six numbers because there is not going to be a visit ID of six numbers. There's only going to be a visit ID of four numbers. Keep on going. We're going to at least also change the caption of this to visit space ID, and I think we're good for those two. Now we're going to continue to expand on our fields. We're going to go ahead and create, again, we're dealing with billing, so I'm going to create something called invoice AMT. What's A to MT stand for? We probably have thought in billing, process of elimination, probably dealing with amount. We're going to be dealing with the amount of the invoice. Again, this time, instead of my data type being a short text, in that drop down menu, you see I get a slew of different options. One of those because we're dealing with money is money. You can see that automatically puts that into place. My description, I don't actually need to put anything in here because, well, it's amount, it's currency, but it doesn't have any kind of relationship to any other table. It's a unique element to this table. But I am going to change one thing. Instead of my decimal places, notice my properties have changed here. Here for short text data types, I get all this stuff. For currency, because it's a numerical value, it's a lot more strict. The only things I can really change are things like my decimal places. And instead of auto, I'm going to change this to just two. Two decimal places because sense. I will change my caption from just invoice AMT because I don't know what that is. I'm going to change it to invoice. Amount. That allows me a little bit more understanding of what this one is dealing with. We'll keep on going. Next one is going to be invoice date. All one word again because invoice date now says, well, when did we make the invoice? We again are going to go in and this time we're just going to select the date time data type. And again, you see we get a few different options for our caption. We're just going to say invoice date. And let's take a look at that format option. Right now, format doesn't do much. It's empty. But if we click on the drop down menu for it, you see we get a number of different options of how we want to present this data. Again, just like we learned in Microsoft Excel, dates are this weird hodge podge of numbers and symbols that aren't really alphanumeric short texts. They're their own kind of thing. So I'm just going to go ahead and say short date, month, day, year for the US kind of timestamp. We're going to continue on. And we're going to go ahead and add in one more option, invoice paid. Has this invoice been paid or not? Well, that sounds like a yes or no question, which sounds like another one of our data types, yes or no. And you can see, again, we have even smaller properties because we're dealing with something very strict. It can only be yes or no. So only things I can really change are maybe what it means to be yes or no, true or false, on and off, and my caption invoice paid. And once we've built this out, we do need to save this. We need to go ahead and click our little floppy diskette. We're going to go ahead and call this one. We'll go ahead and call it invoice table since we got a lot of invoice words here, invoice, invoice, invoice, invoice. And to change the view, to change how this looks, notice over here on our left, we have that table, that view, that option. If I just simply click on this, you see that it switches over from our table design view. Again, you can actually see the symbol changes as well. And I can click on it again, and it goes back to it. I can go back and forth from these. And so now I'm able to adjust these. Now, they're a little cut off, so I can resize these a bit. And what you'll see is all those captions we wrote, they now appear as well.