WEBVTT 00:03.730 --> 00:06.550 Hey did everyone that they share and welcome to another video. 00:06.550 --> 00:09.270 And in this video, again, we are going to talk about three. 00:09.280 --> 00:10.810 I know you love to write code. 00:10.810 --> 00:12.070 I also love to write code. 00:12.070 --> 00:16.630 In fact, in majority of my courses, I like to just go through into the code later and write that. 00:16.630 --> 00:18.040 But this is interesting theory. 00:18.040 --> 00:19.120 This is important theory. 00:19.120 --> 00:22.360 You should know about it, otherwise you'll be mindlessly writing the code. 00:22.360 --> 00:23.290 We don't want that. 00:23.290 --> 00:27.040 We want you to write code efficiently by full understanding of it. 00:27.220 --> 00:32.740 So let's talk about MongoDB in depth and what Mongoose role does at play and why this business logic 00:32.740 --> 00:35.050 comes into the picture even at the first place. 00:35.170 --> 00:40.630 So imagine this is your MongoDB and this is where you want to store all of your data persistently. 00:40.630 --> 00:42.550 So this is how it looks like. 00:42.550 --> 00:48.220 Assume that your MongoDB usually it gives a kind of abstraction when you install it onto your same computer, 00:48.220 --> 00:49.630 but it's not like that. 00:49.630 --> 00:54.760 This whole box denotes that MongoDB is installed onto some another computer, some another machine, 00:54.760 --> 00:57.370 and that's where this MongoDB is now. 00:57.370 --> 01:03.490 The picture where MongoDB can come in, you can directly talk to it or you can inject a mongoose. 01:03.670 --> 01:10.090 The mongoose is again an ODM, which helps you to interact with MongoDB with easier methods and some 01:10.090 --> 01:14.350 of the precooked method that are already there in Mongoose, which you are going to study in this video 01:14.350 --> 01:17.440 and I'll show you some of the clean examples that Mongoose gives you. 01:17.470 --> 01:18.880 Can you work without Mongoose? 01:18.910 --> 01:19.630 Absolutely. 01:19.630 --> 01:23.650 But you have to write all of your validation code and all the checks that are being given to you. 01:23.680 --> 01:26.740 Mongoose helps you to write all these checks right out of the box. 01:26.740 --> 01:29.080 And that's thus it saves so much of the time. 01:29.080 --> 01:35.200 With us now, another question that usually I get is let's say this is the web and it is sending all 01:35.200 --> 01:39.280 the data to us, like in the request body or the forms that we have on the front end are probably in 01:39.280 --> 01:39.910 the react. 01:39.910 --> 01:45.240 So we can directly use Mongoose or maybe we can directly throw that into the database itself. 01:45.370 --> 01:48.430 No, that's where you would be absolutely horribly wrong. 01:48.430 --> 01:53.560 It's like almost you buy the food from the market and you flush it down directly to the toilet. 01:53.590 --> 01:54.910 No, you don't do that. 01:54.910 --> 02:00.070 We always go ahead by the food, we process the food, we cook it and we digest it and then it goes 02:00.070 --> 02:00.520 down. 02:00.520 --> 02:05.440 So again, make sure you understand your data needs to be processing first and then throw it up into 02:05.440 --> 02:08.800 the database without the back end or without the business logic. 02:08.800 --> 02:11.080 You cannot just dump the data itself. 02:11.080 --> 02:15.400 I know it's a weird example, but it always stuck with the student and the always remember throughout 02:15.400 --> 02:15.910 the life. 02:15.910 --> 02:21.460 So that is why whenever the data comes up, whether it's coming from React, mobile application, react, 02:21.460 --> 02:25.720 flutter, whatever is your favorite one, you go ahead and add this into the back end. 02:25.720 --> 02:28.540 And this is what we are designing so far into the picture. 02:28.540 --> 02:31.870 So once this actually comes in, then you add some of the business logic. 02:31.870 --> 02:36.040 Maybe you want to authenticate whether somebody has passed on an email, which is a correct email, 02:36.070 --> 02:40.900 correct format or not, your password is fully secured or not, or at least you are using six digits 02:40.900 --> 02:41.590 or something. 02:41.590 --> 02:43.930 So you perform all those validation first. 02:43.930 --> 02:48.880 Once those all validation are done, you have massaged your data, fixed all of the data that whatever 02:48.880 --> 02:53.410 you want to do it, and then after that you talk to the mongoose and say, Hey, Mongoose, I want to 02:53.410 --> 02:56.710 add some data into the database on top of my validation. 02:56.710 --> 02:58.510 Can you add your validations also? 02:58.510 --> 03:03.040 Can you also give me some easier method to do the current operation in the database? 03:03.040 --> 03:08.770 And that's where Mongoose helps you and actually go ahead and finally sends all the data to the MongoDB. 03:08.800 --> 03:11.980 Now, one final advice that I would like to 100% give you. 03:11.980 --> 03:17.110 Please always remember this you will never face any trouble in the database is remember that your database 03:17.110 --> 03:19.120 is always on different continent. 03:19.150 --> 03:20.230 No, it is not. 03:20.230 --> 03:22.930 In the ideal case, you want to keep it on the same continent. 03:22.960 --> 03:27.220 If you are using eight US or something, you probably be having database in Mumbai or something. 03:27.220 --> 03:32.230 But I always recommend all of my student to assume that it's on different databases, different continent 03:32.230 --> 03:32.710 itself. 03:32.710 --> 03:33.700 Why is it so? 03:33.700 --> 03:38.440 Because once you understand that your database is on a different continent, you will always remember 03:38.440 --> 03:43.690 that it takes time when you add some data into the database or retrieve some data from the database. 03:43.690 --> 03:48.730 So it always, no matter what, it goes into a sink and a weight or any kind of similar situation. 03:48.730 --> 03:51.670 Remember, it is going to take some time in your local development. 03:51.670 --> 03:57.880 It's instance, it's really fast and the world has also brought up into the world where we are not that 03:57.880 --> 03:58.420 much patience. 03:58.420 --> 04:00.160 So remember, patience is the key. 04:00.160 --> 04:05.080 Whatever you do, database is on different continent and when the data will travel, it will take some 04:05.080 --> 04:05.410 time. 04:05.410 --> 04:06.790 So always remember that. 04:06.910 --> 04:11.650 Okay, now that you understand this, let's also go into the Odiham section Mongoose. 04:11.680 --> 04:16.330 Now this is where we are going to learn about the elegant MongoDB object modeling. 04:16.330 --> 04:18.610 We will have a separate video on modeling itself. 04:18.610 --> 04:20.020 Don't you worry on that part. 04:20.020 --> 04:23.830 So let's go ahead and see read the docs that how we can actually read the docs. 04:23.860 --> 04:27.820 Now, first and foremost, I will show you how to connect the database and all of that. 04:27.820 --> 04:29.500 We'll have a detailed video on this. 04:29.500 --> 04:31.090 But right now, let's talk about that. 04:31.090 --> 04:33.130 This is a blog schema that they are giving. 04:33.130 --> 04:36.610 So let's just say you want to design a blog and this is how you can do it. 04:36.610 --> 04:41.230 So notice here, it's really, really easy in this case that you are saying, okay, it's not really 04:41.230 --> 04:41.560 big. 04:41.560 --> 04:43.300 The blog is going to have a title. 04:43.300 --> 04:47.080 And schema, by the way, is the structure of how your data is going to look like. 04:47.080 --> 04:51.640 Every application has a structure, your blog has image, title, subtitle and a content. 04:51.640 --> 04:53.410 So and who is the author of that? 04:53.410 --> 04:57.280 So everything needs to have a structure and we call that structure as a schema. 04:57.340 --> 05:00.400 So Mongoose helps you to design those schema. 05:00.400 --> 05:01.780 And you can see this is pretty basic. 05:01.880 --> 05:06.200 You'll have a title which will be of type, string author, string body comments and all of that. 05:06.200 --> 05:06.950 So pretty. 05:06.960 --> 05:09.940 Okay, there is no such extra thing which mongo is giving us. 05:09.950 --> 05:15.710 And yes, I would agree on this point that in this example we don't see the hidden power of the mongoose 05:15.710 --> 05:20.300 that gives us this power actually comes up when you scroll a little bit and look into the validation 05:20.300 --> 05:21.020 section. 05:21.020 --> 05:22.400 Now, right out of the box. 05:22.400 --> 05:25.610 Mongoose gives you so much of the validation that you can use. 05:25.610 --> 05:27.530 For example, in this case the name. 05:27.530 --> 05:29.780 This is a type string, but the required is true. 05:29.780 --> 05:34.940 So this field or this, whenever you're trying to save this into the database, Mongo Mongoose will 05:34.940 --> 05:36.950 alert you that, hey, this value is not there. 05:36.950 --> 05:38.030 This is required. 05:38.120 --> 05:43.040 Not only that, you can actually scroll it a little bit and you can see that you can actually provide 05:43.040 --> 05:49.040 the custom messages even that this X the type is number and the minimum is there and the max is there. 05:49.040 --> 05:51.440 So you have to choose between six and 12. 05:51.440 --> 05:55.910 And if you don't choose anything or if you choose anything else, then a custom message can be written 05:55.910 --> 06:00.890 directly into the model that Hey, it must be at least six eggs and you are choosing the less one. 06:00.890 --> 06:05.690 So right out of the box you get the ability to check the things right out of the box. 06:05.690 --> 06:11.180 No custom validation we have written and we can also send an error message which is stored in the central 06:11.180 --> 06:13.250 model of the entire database. 06:13.250 --> 06:14.300 So this is so good. 06:14.870 --> 06:18.590 Now we also have some of the unique capabilities to find out whether it is unique or not. 06:18.590 --> 06:21.440 And they also give you some warnings in case you want to check that out. 06:21.440 --> 06:24.320 But you can also go ahead and write your custom validators. 06:24.320 --> 06:29.600 If you know about the regex or the regular expression, you can write your custom regex and can test 06:29.600 --> 06:31.040 your values for this. 06:31.040 --> 06:32.450 What are the values coming in? 06:32.450 --> 06:34.100 And then you can return based on that. 06:34.100 --> 06:38.660 The message that, hey, this is not a valid phone number or whatever, so this is just the start of 06:38.660 --> 06:40.430 it that what mongoose actually can do. 06:40.430 --> 06:46.970 You you can also look for the queries, by the way, the queries are the simple way that there are few 06:46.970 --> 06:48.740 operations in the database, not too many. 06:48.740 --> 06:53.570 You just create new values or you just go ahead and search for them or query with that. 06:53.570 --> 06:58.370 And further down the road you can query to update, you can query to delete whatever you want to do. 06:58.370 --> 07:00.770 And these are the only methods that you have to study. 07:00.770 --> 07:02.240 And these are really, really short. 07:02.240 --> 07:07.850 You have to just delete some operations you can find by ID or some values that you can pass on or you 07:07.850 --> 07:09.470 can find and delete, find an update. 07:09.470 --> 07:14.480 So these are not too many compared to what actually you have to learn if you are learning the entirety 07:14.480 --> 07:15.260 of the database. 07:15.260 --> 07:17.630 So this helps me so much here. 07:17.660 --> 07:23.060 Now coming back up to there, you can also go ahead for connections and can do so much on the connection. 07:23.060 --> 07:28.370 There are even hooks provided that if I'm saving the data into the database before saving the data, 07:28.370 --> 07:33.530 do this operation or just after saving the data, do that operation so there can be lifecycle hooks 07:33.530 --> 07:35.000 available with the mongoose. 07:35.000 --> 07:39.380 I know this is too much of the information for you right now, and especially when I'm talking in the 07:39.380 --> 07:44.240 theory this is not making too much of sense, but eventually this is going to make sense. 07:44.240 --> 07:48.500 The reason why I'm putting this theory out right now, because when we'll be doing the actual practical, 07:48.500 --> 07:51.770 then this theory will get recalled and you will get more understanding. 07:51.770 --> 07:55.070 So this is a proven theory that I've used again and again while the teaching. 07:55.070 --> 07:56.450 So this is how we are going to do it. 07:56.540 --> 07:59.180 So again, we will be coming back on to the documentation. 07:59.180 --> 08:00.800 We'll be seeing that how we can do it. 08:00.800 --> 08:05.510 Right now, what I want to do is go ahead and explore the schema part because that's what we'll be designing 08:05.510 --> 08:07.160 that how we can define the schema. 08:07.160 --> 08:08.120 So go ahead. 08:08.120 --> 08:10.490 Creating a model, how we can do that and all of this. 08:10.490 --> 08:15.860 This will help you a little bit when we are going to actually start our project and write the code. 08:15.860 --> 08:18.920 So this is all the basics that I wanted to discuss with you. 08:18.920 --> 08:23.210 In the next video, I will talk a little bit about the data modeling and what the schema design and 08:23.210 --> 08:23.960 all of that. 08:23.960 --> 08:29.150 I will show you what kind of tools are actually used in the industry or in the production grade, and 08:29.150 --> 08:34.280 I'll show you what alternatives we can use because we don't want to buy them, at least for this course. 08:34.280 --> 08:36.200 Let's go ahead and catch up in the next video.