WEBVTT 00:00.120 --> 00:06.680 OK so next up in this onslaught of data types we're going to discuss some important numeric types. 00:06.780 --> 00:10.460 So there are quite a few We've already discussed it. 00:10.500 --> 00:12.070 We've used it quite a bit. 00:12.210 --> 00:17.640 It works with whole numbers so it's useful if you're working with things where you need them or want 00:17.640 --> 00:21.320 them to be whole numbers where decimals don't matter. 00:21.330 --> 00:24.420 So we know how it works at this point. 00:24.480 --> 00:29.020 However there are bunch of other data types set my ask to come up with. 00:29.070 --> 00:30.660 We're not going to talk about every single one. 00:30.690 --> 00:33.660 We're just going to talk about the ones that will matter the most. 00:33.660 --> 00:42.270 And in my opinion those are the first one is decimal so decimal is what it sounds like it's a number 00:42.450 --> 00:45.420 that includes a decimal afterwards. 00:45.860 --> 00:48.290 How can I put this thing gets the right way of saying it. 00:48.350 --> 00:51.080 It's a number that includes a decimal point and something after it right. 00:51.080 --> 00:52.740 Can it includes a B after it. 00:52.740 --> 00:57.660 So then we create a column we actually provide two arguments and I'll talk about those in just a moment. 00:57.660 --> 01:04.200 But the important part here is that it's a way of creating a column that will store numbers that include 01:04.200 --> 01:06.630 decimals something after the decimal point. 01:06.630 --> 01:08.880 So what are these two numbers we're passing in. 01:09.150 --> 01:12.660 Well on this next slide I have a handy little graphic here. 01:12.720 --> 01:18.390 When we run or when we create a column let's say let's call it price. 01:18.390 --> 01:20.310 This is a price of a. 01:20.550 --> 01:20.970 I don't know. 01:21.030 --> 01:23.270 Let's work with books or books price. 01:23.670 --> 01:31.760 We have two different arguments the first one five tells my to all the maximum number of digits that 01:31.760 --> 01:32.980 our number can have. 01:33.260 --> 01:40.010 So that actually includes both before and after the decimal point and then the second number is how 01:40.010 --> 01:43.700 many digits come after the decimal point. 01:43.700 --> 01:47.240 So another way of looking at it something like this. 01:47.240 --> 01:51.290 Here's the maximum number we can store in a decimal 5. 01:51.290 --> 01:52.080 Comment too. 01:52.280 --> 01:55.060 So it's five digits long. 01:55.160 --> 01:58.540 Two of those digits are after the decimal point. 01:58.640 --> 02:05.330 And if we hop over to the documentation which I'll try and hold my tongue but I definitely find to be 02:05.330 --> 02:09.600 occasionally subpar it does an OK job here explaining it. 02:09.620 --> 02:16.920 So the declaration syntax for a decimal column is decimal em comedy M is a maximum number of digits 02:16.920 --> 02:20.020 of precision it can go up to 65. 02:20.360 --> 02:23.440 D is a number of digits to the right of the decimal point. 02:23.570 --> 02:30.160 Also called the scale I never heard anyone actually used those terms but I guess it's good to know. 02:30.560 --> 02:38.390 And it has a range of 0 to 30 so there can be no more than 30 digits after the decimal point which in 02:38.390 --> 02:41.230 most cases is going to be plenty. 02:41.260 --> 02:45.450 I mean way way way more than you pretty much ever need. 02:45.590 --> 02:50.700 So that's the gist of decimal here is to store numbers and decimals. 02:50.720 --> 02:55.330 But we do need to specify roughly what those numbers need to look like. 02:55.520 --> 03:02.900 So we'll create a very simple table that say a generic item so items and all we're going to have is 03:02.900 --> 03:03.420 a price. 03:03.430 --> 03:05.390 We don't you worry about a name or anything. 03:05.450 --> 03:08.550 So we'll have a column called price which is a decimal. 03:08.930 --> 03:14.480 And let's go with what we saw there 5 comment too just like that. 03:15.510 --> 03:16.020 OK. 03:16.190 --> 03:16.990 So we have that. 03:17.000 --> 03:19.700 Now let's insert a couple of things and test it out. 03:19.700 --> 03:28.230 So insert into items the first one that will do when you specify price and then values. 03:28.490 --> 03:37.330 And the first one will be just a whole number let's say 7 just like that. 03:37.340 --> 03:55.890 OK then let's do a long number like that see that we get a warning then let's do thirty four point eight 03:56.130 --> 04:05.810 eight and let's also do a two nine eight point nine nine nine nine. 04:06.260 --> 04:12.320 And finally let's do one point nine nine nine nine. 04:12.630 --> 04:17.950 OK so now let's do our Slyke star from items and see what we have. 04:18.420 --> 04:19.130 OK. 04:19.440 --> 04:27.150 So the first thing that you'll notice is when we inserted 7 with our decimal it added those two decimal 04:27.630 --> 04:28.770 places for us. 04:28.770 --> 04:35.220 And again that's because when we created the table we said there are two places after the decimal. 04:35.760 --> 04:38.700 So it adds those in even if it's a nice whole number. 04:38.700 --> 04:40.320 The next one is a bit weird. 04:41.400 --> 04:44.420 We never inserted nine nine nine point nine nine. 04:44.790 --> 04:48.410 We inserted seven nine eight seven six five four. 04:49.020 --> 04:55.050 So what's happening here is that this is much larger than the maximum number allowed the maximum number 04:55.050 --> 04:55.370 allowed. 04:55.380 --> 05:02.820 As you can see here is nine nine nine point nine nine because we specified it's five digits total with 05:02.820 --> 05:04.710 two coming after the decimal. 05:04.710 --> 05:08.010 So that gives just ninety nine point nine nine. 05:08.100 --> 05:10.080 So good to know when you do this. 05:10.170 --> 05:15.260 If you create a number is too large it's going to just put the largest possible decimal. 05:15.270 --> 05:16.950 Given the constraints you set up. 05:17.220 --> 05:22.200 The next step we have our thirty four point eight which looks just the same. 05:23.390 --> 05:26.870 And then we have two nine eight point nine nine nine nine. 05:27.230 --> 05:32.330 Which you'll notice here is actually rounded up so it's rounded to 2 9 9. 05:32.340 --> 05:35.900 And that's because we specified rounding to two decimal places. 05:36.120 --> 05:40.830 And when we do that it's going to round up and that will round up and so on. 05:41.030 --> 05:43.180 Well actually it's on this one here. 05:43.290 --> 05:46.620 It will round up to nine nine point 0 0. 05:46.620 --> 05:50.830 Same thing applies here or we have one point nine nine nine nine. 05:51.180 --> 05:55.820 So that's the basics of the Decimal data type pretty commonly used. 05:55.830 --> 05:58.950 All I'll be using it throughout the course. 05:58.950 --> 06:03.870 With that said there are other data types that we can use to do the same thing that we're going to talk 06:03.870 --> 06:07.570 about in the next video and we'll discuss why and when you would use each one.