WEBVTT 00:00.360 --> 00:01.110 All right. 00:01.110 --> 00:04.770 So we saw how we can create databases and destroy them. 00:04.770 --> 00:06.650 So what comes next. 00:07.110 --> 00:09.120 We're going to see how we actually use them. 00:09.420 --> 00:12.690 And I mean that in a very literal sense in my as well. 00:12.750 --> 00:21.000 There is a use command and what this does is it tells me as well which database we want to be working 00:21.000 --> 00:21.780 with. 00:21.810 --> 00:29.520 So we have potentially 10 different databases on one my a school server and we want to search some data 00:29.520 --> 00:30.440 from one of them. 00:30.690 --> 00:36.420 What we need to tell my as well which one we want to be using at any given time and we can switch between 00:36.420 --> 00:40.330 them using the use command that you see right here. 00:41.070 --> 00:43.840 So really quickly show you how it works over in cloud 9. 00:44.220 --> 00:45.870 So if we create a new database 00:48.640 --> 00:55.850 then we'll just call this one dog walking app and we hit enter. 00:56.220 --> 00:59.050 We do show databases. 00:59.340 --> 01:00.830 There it is. 01:00.840 --> 01:10.180 And if I want to use that all I have to do is type use dog walking app and you won't see much except 01:10.180 --> 01:12.730 for database changed. 01:13.210 --> 01:14.030 That's a good thing. 01:14.260 --> 01:19.660 But if we wanted to know for sure what database we are currently using there there's another in my escarole 01:19.660 --> 01:26.430 command that we can use that command looks like this select database with parentheses after it. 01:26.600 --> 01:30.220 And what this will do is tell you the currently used database. 01:30.250 --> 01:31.240 So let's try that out. 01:31.240 --> 01:32.540 Back in cloud 9. 01:32.830 --> 01:41.380 If I type select database with those parentheses and a semi-colon that tells me database is dog walking 01:41.380 --> 01:51.340 app and if I decided to delete that database I would use the drop database dog walking app command. 01:52.140 --> 02:00.280 It tells me queery OK I do show databases and it should be gone but if I do my select database command 02:01.180 --> 02:06.670 pause and think to yourself for a moment what database do you think I'll be using right now. 02:06.670 --> 02:11.440 We were using the dog walking app but then we deleted it. 02:11.440 --> 02:14.430 So now what. 02:14.620 --> 02:16.010 And here's the answer. 02:16.090 --> 02:17.310 Kind of a trick question. 02:17.320 --> 02:22.870 We're not using a database right now and the no here and we'll be talking a bit more about NO throughout 02:22.870 --> 02:26.670 this course but that basically means we're not using any database. 02:26.710 --> 02:29.190 So just to show you one more time if we switch. 02:29.230 --> 02:33.970 Let's say I wanted to use one of these preexisting ones like the C-9 database. 02:34.000 --> 02:35.270 I'm not going to do that. 02:35.830 --> 02:40.060 But if I wanted to I just use C9. 02:40.240 --> 02:42.160 And now if I do my select database 02:45.080 --> 02:47.620 tells me database is se'nnight. 02:47.900 --> 02:51.080 OK so that's all there is to using a database. 02:51.260 --> 02:55.490 And then also this select database command to see your current database. 02:55.490 --> 03:00.510 Next up we'll start talking about tables and putting some data in these databases as soon as possible.