WEBVTT 00:07.730 --> 00:10.670 I will call you back again to another lecture in MySQL. 00:10.670 --> 00:15.740 And in this video lecture let's go ahead and look at wildcard characters. 00:15.740 --> 00:19.910 So in MySQL we have the percentage and we have the underscore. 00:19.910 --> 00:27.740 And both of these characters helps us a lot in order to do some important job in our queries. 00:27.740 --> 00:35.480 So in MySQL you want to be able to find maybe a specific character or a character that started with 00:35.480 --> 00:37.820 a this or that. 00:37.850 --> 00:40.610 Then you go ahead and use the wildcard characters. 00:40.610 --> 00:46.370 So the wildcard characters helps us to substitute one or more characters in a string. 00:46.610 --> 00:46.910 All right. 00:46.910 --> 00:50.780 So I'm using the word characters and most of us will be like, what is going on? 00:50.780 --> 00:51.770 What is happening? 00:51.800 --> 00:54.710 Let's go ahead and give an example of this. 00:54.740 --> 00:58.790 Let me say I want to check the first name or the last name. 00:58.790 --> 01:01.790 Then I want the name that started with P. 01:01.820 --> 01:10.240 Every name that does similar with P or names that start with A or B, S, m, Q, or z for the first 01:10.270 --> 01:11.650 name or for the last name. 01:11.650 --> 01:18.040 I want the names that started with a, j, C, R, S, or g. 01:18.190 --> 01:20.560 Now how can you be able to do this? 01:20.560 --> 01:26.830 So I know as a beginner you might be like, okay, I can be able to select that maybe row and say select 01:26.830 --> 01:29.710 all from your students table. 01:30.640 --> 01:30.940 But why? 01:30.940 --> 01:32.770 So at this point just t correct. 01:32.800 --> 01:34.210 Then let's move ahead and check it out. 01:34.240 --> 01:37.000 Now let's add a Y or a week class. 01:37.000 --> 01:41.800 And most of us would be like okay, let's go here and see where the first name or the last name is the 01:41.800 --> 01:43.030 one you want to check out. 01:43.060 --> 01:47.440 Maybe the first name is equal and let me see. 01:47.470 --> 01:51.760 Want to check for the one that starts with Z. 01:51.790 --> 01:54.850 So if I go ahead and insert Z right in there. 01:54.880 --> 02:00.340 So if you ever do that it means that you want to return nothing. 02:00.400 --> 02:01.360 Let's go ahead and check that out. 02:01.360 --> 02:01.540 No. 02:01.540 --> 02:07.770 If something would be printed out for us Now, if I execute the query and you can see the tables are 02:07.770 --> 02:08.310 empty. 02:08.340 --> 02:09.300 Why? 02:09.690 --> 02:14.490 Now what you need to do is when you're using the white characters, you don't use the equal sign. 02:14.490 --> 02:17.760 You use what is called the keyword known as like. 02:18.000 --> 02:25.860 And when you use like, then you go ahead and use one of these characters, the percentage or the underscore. 02:25.860 --> 02:33.780 And if you want to get the names that started with Z, you go ahead and use the percentage. 02:33.780 --> 02:41.130 So and because we want to understand with Z and not the one that ends with Z, go ahead and put the 02:41.130 --> 02:43.080 percentage at the back. 02:43.080 --> 02:47.430 Because if z comes first, it will return the one that started with z. 02:47.460 --> 02:51.840 What is z comes last, it will return the one that starts with that ends with z. 02:51.870 --> 02:53.010 Go ahead and check it out. 02:53.640 --> 02:58.440 So I have gender and you can see Z started with a z. 02:58.740 --> 03:02.610 And let's go ahead and check out maybe Peter. 03:02.610 --> 03:06.420 And let's go ahead and run this and check it out Peter. 03:06.440 --> 03:09.440 know if I want to check out. 03:09.470 --> 03:13.760 Maybe I want the one that stay with R if I run this. 03:13.790 --> 03:16.580 Let's go ahead and put R here and check out this. 03:16.610 --> 03:22.340 We don't have any first name associated with R, but let's go ahead and place this R at the back of 03:22.340 --> 03:28.220 this and check out what we need to get now is the ones that ends with R. 03:28.220 --> 03:31.760 So it's going to be the one that ends and no one hit wonder status. 03:31.760 --> 03:36.140 So if your R goes at the back of the percentage it means one at ends. 03:36.140 --> 03:40.040 But if the R comes in the front, it means the one that started with R. 03:40.070 --> 03:42.950 But now I want to check for the ones that ends with R. 03:42.980 --> 03:45.230 Then go ahead and run this and check it out. 03:45.410 --> 03:49.790 We have pizza, Oscar and Lucinda in that same way. 03:49.820 --> 03:58.550 I'll go ahead and change this to last name and let's check if we have last name that ends with R, and 03:58.550 --> 03:59.870 go ahead and execute this query. 03:59.900 --> 04:01.040 We don't have anyone. 04:01.070 --> 04:07.070 Well let's go ahead and change that to E and check if we have last name that ends with R. 04:07.670 --> 04:08.990 And this is the cutest query. 04:09.040 --> 04:09.580 we have. 04:09.610 --> 04:11.470 Jude and Grace. 04:12.190 --> 04:17.920 Now let's go ahead and, uh, place this, uh, right in here. 04:17.950 --> 04:21.640 I don't even know if we have the first name that started with E. 04:21.820 --> 04:23.290 The last name does start with E. 04:23.440 --> 04:24.280 I have to check. 04:24.310 --> 04:25.660 We don't have anyone. 04:25.660 --> 04:30.790 Well, let's go ahead and put that something like H because I believe we have H and check out this. 04:30.790 --> 04:32.650 So we have last name. 04:32.680 --> 04:33.400 Hillary. 04:33.430 --> 04:34.840 Hillary center with H. 04:34.870 --> 04:37.810 What if we go back and place this at the back? 04:37.840 --> 04:41.350 It means we're looking for the last name that ends with H. 04:41.380 --> 04:43.120 Go ahead and check it out. 04:43.150 --> 04:44.620 We have Smith. 04:44.650 --> 04:47.080 So Smith ends with H. 04:47.110 --> 04:50.740 So it is in a way it's a wild card in MySQL. 04:50.740 --> 04:53.920 And uh I hope that is very, very cool. 04:53.950 --> 04:58.330 Now what if we go ahead and add more characters. 04:58.360 --> 04:59.500 Let's go ahead and see. 04:59.500 --> 05:05.020 We want the one, maybe the last name that started with, uh, p a. 05:05.170 --> 05:05.950 I don't even know. 05:05.980 --> 05:07.120 What if we have that? 05:07.150 --> 05:08.770 Let's go ahead and check this out. 05:08.980 --> 05:10.240 We don't ever have that. 05:10.270 --> 05:12.270 But let's say we have James G. 05:12.360 --> 05:14.250 So let's go ahead and check it out. 05:14.880 --> 05:22.950 So oh we don't have anyone that started with a let's go ahead and show our table again so we can start 05:22.950 --> 05:23.670 from there. 05:23.700 --> 05:24.060 Okay. 05:24.060 --> 05:25.710 We have Jude and not James. 05:25.710 --> 05:27.690 So go ahead and place this back again. 05:27.690 --> 05:29.760 And let's go ahead and change this to Jew. 05:29.760 --> 05:31.200 And let's check it out. 05:31.200 --> 05:32.340 So we have Jude. 05:32.340 --> 05:35.670 And Jude starts with a j u. 05:35.670 --> 05:37.410 So now we can add more. 05:37.410 --> 05:39.810 And that go ahead and print out for you. 05:40.230 --> 05:40.620 All right. 05:40.620 --> 05:48.210 Let's go ahead and check in Roman dates that enroll within 2092 or 2091. 05:48.210 --> 05:54.150 What we need to do is go over here and change this last name and change the last name a while and see 05:54.930 --> 05:57.420 a row underscore date. 05:57.810 --> 06:06.480 Uh, I want to leave the percentage, and I'm going to say this is a 2092 and go ahead and check it 06:06.480 --> 06:07.080 out. 06:07.320 --> 06:12.330 So Oscar enrolled in 2092 out of 2091. 06:12.360 --> 06:13.610 Go ahead and check it out. 06:14.690 --> 06:20.240 So we have a Barack and Sarah in row in 2091. 06:20.240 --> 06:22.610 So this is the way you use the white cat character. 06:22.610 --> 06:27.500 So there's another character that is remaining and that is the underscore the underscore white character 06:27.530 --> 06:30.710 we use to return any random character. 06:30.710 --> 06:35.780 So let's go ahead and find any department with random character length. 06:35.780 --> 06:38.540 So number here and see where department. 06:38.540 --> 06:40.790 So I'm going to use the underscore right now. 06:42.200 --> 06:52.580 So department and uh go right in here and see underscore then length. 06:52.610 --> 06:58.160 Then let's go ahead and execute this query and check if that will get anything for us. 06:58.160 --> 07:04.730 And then what happens here is we have electrical we have electronics. 07:04.760 --> 07:05.360 All right. 07:05.360 --> 07:11.930 So all I need to do is I'll go over and let's say maybe electronics. 07:11.990 --> 07:12.620 All right. 07:12.650 --> 07:14.870 Now go ahead and execute this query. 07:15.140 --> 07:16.490 and the electronics. 07:16.490 --> 07:22.190 So if you want to remove the last one, because the reason why I removed it is that you're going to 07:22.190 --> 07:26.300 replace the ones you didn't show with white characters on the score. 07:26.330 --> 07:33.740 Let's go ahead and say, if I want to just show this, I'm going to say I will have a one, two, three, 07:33.740 --> 07:35.030 four, five, six. 07:35.030 --> 07:41.510 So I'm going to replace these six characters with underscore, say one, two, three, four, five, 07:41.510 --> 07:41.990 six. 07:41.990 --> 07:44.510 Then go ahead and execute this query and check it out. 07:44.870 --> 07:45.740 Electronics. 07:45.740 --> 07:54.440 So if I remove one of it and run this code I have electric car because the electric car is five after 07:54.590 --> 07:55.820 after the length. 07:55.880 --> 08:01.190 So this is how this works because I want to take it one step at a time if I want to check out. 08:01.190 --> 08:05.480 So go ahead and say I want maybe Silverstone I will see. 08:05.510 --> 08:08.750 I'm going to say s underscore. 08:08.780 --> 08:14.300 The first underscore is for C and the second underscore is for I, then VI. 08:14.510 --> 08:17.470 Then if I should run this code let's go ahead and check it out. 08:17.800 --> 08:18.670 Civil. 08:18.880 --> 08:21.550 Then if I should remove l I have to replace that with. 08:21.580 --> 08:23.890 Underscore in order to get civil. 08:23.920 --> 08:25.960 What if I should remove the L? 08:25.990 --> 08:27.490 I'm not going to get anything. 08:27.520 --> 08:28.390 Check it out. 08:28.630 --> 08:30.820 So this is the way you use the underscore. 08:30.850 --> 08:38.140 You're going to also always replace any of the values which you don't want to show with underscore in 08:38.140 --> 08:39.040 order to get that. 08:39.070 --> 08:41.410 Let's go ahead and check in raw date. 08:42.460 --> 08:52.000 So in raw underscore date maybe I want to check out maybe people that enroll on November. 08:52.000 --> 09:01.480 So I'm going to check out the EDA is going to be four characters 2019 or 2018 is A1234. 09:01.510 --> 09:04.330 Then I want to check the error in November. 09:04.480 --> 09:11.290 And I don't want to mind the date they got on the president to underscore one two. 09:11.320 --> 09:13.780 Then go ahead and run this code and check it out. 09:14.080 --> 09:17.830 So now I got the people that enrolled in November and I can see that. 09:17.830 --> 09:26.460 So I have replaced 2091 with our, uh, the full underscores, and I replaced 18 with the two underscore. 09:26.490 --> 09:31.410 Now, if I should go ahead and replace the months with double underscore, then I'll go ahead and say, 09:31.410 --> 09:33.630 maybe I want people to enroll in zero two. 09:33.630 --> 09:35.010 And I don't know if we have that. 09:35.010 --> 09:37.500 Let's go ahead and take it out so we don't have that. 09:37.530 --> 09:39.330 I'll go ahead and cut off these. 09:39.360 --> 09:43.080 Then let's go ahead and run this and check maybe any of the dates. 09:43.080 --> 09:49.620 So we have our date was six 2418 zero one and zero three. 09:49.650 --> 09:55.740 Now if I should go ahead and put this back again I want people that enroll in 24. 09:55.770 --> 09:56.910 Then go ahead and run this. 09:56.910 --> 09:57.810 I check it out. 09:58.470 --> 10:06.690 So I have an Oscar Electrical enroll in 2022, zero seven, 2024. 10:06.720 --> 10:12.720 And if I change that to zero three, I think we have that and we have Zendaya Grace. 10:13.620 --> 10:17.610 So this is a way this, uh, stuff actually works. 10:17.610 --> 10:20.670 And you can actually also combine the two. 10:20.810 --> 10:24.170 Let's let's go ahead and combine the two and see how the two works. 10:24.200 --> 10:26.690 I'm going to say I want a department. 10:26.720 --> 10:28.610 Let's go ahead and put this as a department. 10:30.800 --> 10:33.350 And I'll go ahead and remove this. 10:33.830 --> 10:39.050 So and that department is going to start with anything else. 10:39.050 --> 10:41.900 And then put an L. 10:41.990 --> 10:44.330 Then it starts. 10:46.400 --> 10:47.660 L precede that. 10:47.690 --> 10:48.620 Go ahead and check this out. 10:48.620 --> 10:50.180 Let us know if we have that L. 10:50.180 --> 10:54.410 So the very first one I replaced that with a e, which is the underscore. 10:54.410 --> 11:01.760 And then the anything that comes behind I don't want to put a underscore maybe in it number of times 11:01.760 --> 11:06.950 because it's not going to either return uh, electronics or electrical, because if I should do that, 11:06.980 --> 11:13.190 I have to put seven underscores or six underscores for electronics and five underscore for electrical. 11:13.190 --> 11:14.840 So you can see how this works. 11:14.870 --> 11:21.920 Now what if we have uh, let's go ahead and say I put this to be maybe civil. 11:21.920 --> 11:23.470 And let's go ahead and check this out. 11:23.500 --> 11:25.420 We don't have anything right in here. 11:25.420 --> 11:31.360 So if I should do that, let's go ahead and, uh, put another one maybe. 11:31.390 --> 11:31.780 See. 11:31.810 --> 11:40.420 And I that is then you can go ahead and replace this with a V, then just go ahead and run this and 11:40.420 --> 11:41.140 check it out. 11:41.170 --> 11:42.490 We have civil. 11:42.490 --> 11:48.640 So in that way I was able to replace the PSI with double underscore, then the V then anything that 11:48.670 --> 11:49.450 comes on. 11:49.450 --> 11:51.520 And I want to put that with the underscore. 11:51.550 --> 11:54.640 That is a way to combine these two wild cards. 11:54.640 --> 11:56.050 So go ahead and practice with that. 11:56.050 --> 11:56.920 I hope that is cool. 11:56.920 --> 12:02.410 So to help you to query your table and when you work in large organizations, you can actually use all 12:02.410 --> 12:04.090 these things and see how good they are. 12:04.120 --> 12:05.290 So proud with it. 12:05.320 --> 12:09.130 And if you have any question, please go ahead and use the question and answer section. 12:09.130 --> 12:11.620 And I'm going to get back to you as soon as possible. 12:11.650 --> 12:12.550 Thank you so much. 12:12.550 --> 12:15.430 And I'm going to see you in the next video lecture.