1 00:00:02,520 --> 00:00:04,500 So let's get started with that, 2 00:00:04,500 --> 00:00:08,130 with implementing this kind of structure. 3 00:00:08,130 --> 00:00:09,660 And for this, I first of all 4 00:00:09,660 --> 00:00:12,070 wanna clean up my existing data. 5 00:00:12,070 --> 00:00:15,270 So for that, I'll reach out to restaurants 6 00:00:15,270 --> 00:00:18,850 and run deleteMany and actually pass in 7 00:00:18,850 --> 00:00:20,550 an empty object here, 8 00:00:20,550 --> 00:00:23,880 which is a quick trick for deleting all the documents 9 00:00:23,880 --> 00:00:25,163 in a collection. 10 00:00:27,150 --> 00:00:29,370 You'll of course, rarely wanna do that 11 00:00:29,370 --> 00:00:31,750 because it really erases everything 12 00:00:31,750 --> 00:00:34,660 but here I do wanna do that, to clear it. 13 00:00:34,660 --> 00:00:37,280 Now, with that, I deleted the last remaining restaurant, 14 00:00:37,280 --> 00:00:38,113 which I had. 15 00:00:39,290 --> 00:00:41,290 So now we can start from scratch again 16 00:00:41,290 --> 00:00:44,750 and again, I will start by actually not setting up 17 00:00:44,750 --> 00:00:47,520 by my restaurants but my types. 18 00:00:47,520 --> 00:00:50,890 Again, having that extra types collection is optional 19 00:00:50,890 --> 00:00:54,363 but I explained why I do wanna have it in the last lectures. 20 00:00:55,500 --> 00:00:59,060 So here, I now wanna start by inserting types 21 00:00:59,060 --> 00:01:02,820 and here, I'll insert one new type at a time 22 00:01:02,820 --> 00:01:05,099 and for every type, I wanna have an ID, 23 00:01:05,099 --> 00:01:10,100 which is automatically generated and the name of the type. 24 00:01:10,235 --> 00:01:12,330 So here, since the ID is automatic generated, 25 00:01:12,330 --> 00:01:16,150 we just type name and then this could be German. 26 00:01:16,150 --> 00:01:20,700 We confirm this and then we may be also add Italian 27 00:01:20,700 --> 00:01:23,380 and then maybe also American 28 00:01:23,380 --> 00:01:26,550 and whichever other types of food, 29 00:01:26,550 --> 00:01:28,033 of cuisines you wanna add. 30 00:01:30,400 --> 00:01:33,770 Now with that, with these types inserted, 31 00:01:33,770 --> 00:01:36,120 if I run db.types.find, 32 00:01:36,120 --> 00:01:39,533 we can list all these types and that's now what we got here. 33 00:01:40,730 --> 00:01:42,820 Now we can move on to the restaurants 34 00:01:43,740 --> 00:01:47,700 and here we can use restaurants and again, 35 00:01:47,700 --> 00:01:50,400 insert one new restaurant here. 36 00:01:50,400 --> 00:01:54,433 So again, we define such a JavaScript object, so to say. 37 00:01:55,300 --> 00:01:57,770 The ID will be added automatically 38 00:01:57,770 --> 00:02:00,070 but in addition, we wanna add a name 39 00:02:00,070 --> 00:02:01,730 and then this nested address 40 00:02:01,730 --> 00:02:04,133 and then also the nested type data. 41 00:02:04,990 --> 00:02:07,073 And therefore, I'll start with the name. 42 00:02:07,920 --> 00:02:12,113 Again, let's say I have the Munich Schnitzel House, 43 00:02:13,170 --> 00:02:16,880 then the address, which is this nested object, 44 00:02:16,880 --> 00:02:19,170 So another pair of curly braces, 45 00:02:19,170 --> 00:02:21,270 and then here for that address, 46 00:02:21,270 --> 00:02:25,570 we have the street, food street, let's say. 47 00:02:25,570 --> 00:02:28,850 Then the street number, there is a line break 48 00:02:28,850 --> 00:02:30,660 but again, it's one command. 49 00:02:30,660 --> 00:02:34,910 So a street number, which I'll turn into a string here 50 00:02:34,910 --> 00:02:37,580 because we could have street numbers 51 00:02:37,580 --> 00:02:39,283 like this with annotations. 52 00:02:40,560 --> 00:02:42,500 We have the postal code 53 00:02:42,500 --> 00:02:47,500 and here I'll store this as a number actually, like this. 54 00:02:48,100 --> 00:02:50,620 We could also store it as a string 55 00:02:50,620 --> 00:02:51,850 and that might be better 56 00:02:51,850 --> 00:02:55,690 in case it starts with a leading zero or anything like that 57 00:02:55,690 --> 00:02:58,460 but to also show you how you can store numbers, 58 00:02:58,460 --> 00:03:00,200 this is how you would do it. 59 00:03:00,200 --> 00:03:03,310 You create a number as you would do it in JavaScript 60 00:03:03,310 --> 00:03:05,543 without any quotes or anything like that. 61 00:03:06,830 --> 00:03:08,500 Of course, we also have the city, 62 00:03:08,500 --> 00:03:10,393 which in my case here is Munich. 63 00:03:11,520 --> 00:03:14,470 And then I also have a country, 64 00:03:14,470 --> 00:03:16,663 which in my case here, is Germany. 65 00:03:18,750 --> 00:03:21,120 So that's now the address. 66 00:03:21,120 --> 00:03:25,380 Now, after this address object, this nested object, 67 00:03:25,380 --> 00:03:27,750 I also wanna have the type field 68 00:03:27,750 --> 00:03:30,710 and now that could just be German 69 00:03:30,710 --> 00:03:33,630 but for the reasons mentioned as before, 70 00:03:33,630 --> 00:03:37,470 I will store it actually as a nested object, 71 00:03:37,470 --> 00:03:42,470 where I point at the type ID may be stored like this, 72 00:03:42,860 --> 00:03:45,030 this key name is up to you 73 00:03:45,030 --> 00:03:48,960 and that now should be the ID of the cuisine 74 00:03:48,960 --> 00:03:50,923 I stored in my types collection. 75 00:03:52,050 --> 00:03:55,210 For this, I'll create such an object ID here. 76 00:03:55,210 --> 00:03:59,040 We could also just store it as a string if we wanted to 77 00:03:59,040 --> 00:04:00,640 but I'll create an object ID 78 00:04:00,640 --> 00:04:03,080 by executing this object ID function 79 00:04:03,080 --> 00:04:07,350 and then I'll grab the ID here with the quotes, 80 00:04:07,350 --> 00:04:09,730 from the German type and insert this 81 00:04:09,730 --> 00:04:11,853 between the object ID function. 82 00:04:14,281 --> 00:04:16,190 And then separated by number, comma, 83 00:04:16,190 --> 00:04:19,450 we can insert our name, 84 00:04:19,450 --> 00:04:21,500 so that we don't need to manually 85 00:04:21,500 --> 00:04:23,410 fetch this from the types collection 86 00:04:23,410 --> 00:04:26,100 but so that we have it right here 87 00:04:26,100 --> 00:04:28,980 when we do fetch all our restaurants later 88 00:04:28,980 --> 00:04:30,920 and that's German. 89 00:04:30,920 --> 00:04:33,760 And of course here, I'm entering it on my own again 90 00:04:33,760 --> 00:04:35,380 but as I mentioned before, 91 00:04:35,380 --> 00:04:38,810 if this would be created through some web application 92 00:04:38,810 --> 00:04:42,480 where we use some form for creating restaurants, 93 00:04:42,480 --> 00:04:45,450 then we could fetch the possible allowed values 94 00:04:45,450 --> 00:04:47,070 from the types collection 95 00:04:47,070 --> 00:04:50,890 and pre-populate a dropdown with those values 96 00:04:50,890 --> 00:04:55,230 so that this is actually not a manually entered field. 97 00:04:55,230 --> 00:04:57,020 So that's really just an exception here 98 00:04:57,020 --> 00:04:58,763 because I'm using this shell. 99 00:04:59,750 --> 00:05:02,743 And with that, the first restaurant is done. 100 00:05:03,600 --> 00:05:06,420 If I now hit Enter, this was inserted 101 00:05:06,420 --> 00:05:09,600 and now we can quickly add a second restaurant here. 102 00:05:09,600 --> 00:05:13,643 And let's say this now actually should be a burger house. 103 00:05:14,840 --> 00:05:18,030 So that's the Berlin Burger House. 104 00:05:23,810 --> 00:05:28,810 And the street here is Ham Street 105 00:05:31,610 --> 00:05:36,610 12, let's say, postal code is maybe this. 106 00:05:37,620 --> 00:05:42,230 The city of course is Berlin, country's Germany 107 00:05:42,230 --> 00:05:47,230 and now the type is American, so I'll wrap this ID here. 108 00:05:47,590 --> 00:05:52,590 And then, actually clear this ID 109 00:05:52,980 --> 00:05:54,950 from the object ID function 110 00:05:54,950 --> 00:05:57,110 and paste in that new ID 111 00:05:58,390 --> 00:06:02,423 and replace German here with American. 112 00:06:04,160 --> 00:06:06,963 And then again, hit Enter to insert this. 113 00:06:09,200 --> 00:06:11,370 And with all of that done, 114 00:06:11,370 --> 00:06:15,200 if I now quickly find my restaurants, 115 00:06:15,200 --> 00:06:17,560 here are my restaurant documents 116 00:06:17,560 --> 00:06:20,800 and you can see those nested objects in them 117 00:06:20,800 --> 00:06:23,310 that hold that nested data. 118 00:06:23,310 --> 00:06:25,210 And here, we really see the difference 119 00:06:25,210 --> 00:06:27,240 between no SQL and SQL 120 00:06:27,240 --> 00:06:31,670 because with no SQL, related data is often stored together. 121 00:06:31,670 --> 00:06:32,760 As you can see it here, 122 00:06:32,760 --> 00:06:36,863 instead of split out across multiple tables or collections. 123 00:06:39,770 --> 00:06:41,420 Now with the restaurants added, 124 00:06:41,420 --> 00:06:44,450 I also wanna add some reviews and for this, 125 00:06:44,450 --> 00:06:46,350 this is the plan I came up with. 126 00:06:46,350 --> 00:06:49,060 I wanna have a separate reviews collection 127 00:06:49,060 --> 00:06:51,410 where I have that reviews data 128 00:06:51,410 --> 00:06:55,180 but in there, I'll store a link to the related restaurant 129 00:06:55,180 --> 00:06:58,160 and also the name of the related restaurant, 130 00:06:58,160 --> 00:07:00,400 so that when we fetch the reviews, 131 00:07:00,400 --> 00:07:03,790 we don't need to separately go to the restaurants collection 132 00:07:03,790 --> 00:07:06,720 just to get the names of the related restaurants 133 00:07:06,720 --> 00:07:09,570 but that instead the names are stored together 134 00:07:09,570 --> 00:07:12,070 with the reviews, so that whenever we show 135 00:07:12,070 --> 00:07:16,090 a list of reviews, we can run one query, one command 136 00:07:16,090 --> 00:07:17,640 to get all the reviews 137 00:07:17,640 --> 00:07:19,820 and then also have the restaurant names 138 00:07:19,820 --> 00:07:21,803 already with that response. 139 00:07:22,840 --> 00:07:27,520 So therefore, we can now go to db.reviews 140 00:07:27,520 --> 00:07:29,840 and actually, first of all, 141 00:07:29,840 --> 00:07:33,380 I'll reach out to restaurants and run FindOne 142 00:07:33,380 --> 00:07:37,390 with an empty object to simply find that first restaurant, 143 00:07:37,390 --> 00:07:40,440 because I'll need its ID in a second. 144 00:07:40,440 --> 00:07:42,940 And then I'll go to the reviews collection, 145 00:07:42,940 --> 00:07:44,220 which doesn't exist yet 146 00:07:44,220 --> 00:07:47,470 but which will be created on the fly, as you learned 147 00:07:47,470 --> 00:07:51,810 to insert a new review, like this. 148 00:07:51,810 --> 00:07:53,450 Now here for the reviews, 149 00:07:53,450 --> 00:07:57,300 we wanna have the name of the person who left the review. 150 00:07:57,300 --> 00:08:00,810 The ID will be created automatically, as you learned. 151 00:08:00,810 --> 00:08:02,050 We wanna have the rating, 152 00:08:02,050 --> 00:08:05,230 which should be a number between one and five. 153 00:08:05,230 --> 00:08:07,960 And then, we also wanna have the text 154 00:08:07,960 --> 00:08:11,610 that describes the review, or that explains the review. 155 00:08:11,610 --> 00:08:13,680 Then a date when the review was left 156 00:08:13,680 --> 00:08:15,283 and then the restaurant data. 157 00:08:16,220 --> 00:08:20,000 Now, let's add their reviewer data 158 00:08:20,000 --> 00:08:25,000 and that could just be something like Max Schwarzmuller. 159 00:08:25,050 --> 00:08:26,550 Alternatively, of course, 160 00:08:26,550 --> 00:08:29,340 that could also be some nested object 161 00:08:29,340 --> 00:08:32,570 where you then have a first name, Max 162 00:08:32,570 --> 00:08:37,570 and a last name, Schwarzmuller. 163 00:08:38,360 --> 00:08:41,230 It really depends on how you wanna fetch 164 00:08:41,230 --> 00:08:42,730 and store that data. 165 00:08:42,730 --> 00:08:45,960 That depends on the application you're building. 166 00:08:45,960 --> 00:08:48,300 To show you that you could store it like this, 167 00:08:48,300 --> 00:08:49,830 I will store it like this 168 00:08:49,830 --> 00:08:52,140 but just storing it as one string, 169 00:08:52,140 --> 00:08:54,560 instead of this kind of nested object 170 00:08:54,560 --> 00:08:56,173 would also have been fine. 171 00:08:57,210 --> 00:08:58,260 And theoretically, 172 00:08:58,260 --> 00:09:00,400 you can also store it in different ways 173 00:09:00,400 --> 00:09:03,130 in your different documents in that collection, 174 00:09:03,130 --> 00:09:05,930 though even though you have that flexibility, 175 00:09:05,930 --> 00:09:09,310 you'll of course typically wanna use a similar structure, 176 00:09:09,310 --> 00:09:11,240 so that when you fetch the data, 177 00:09:11,240 --> 00:09:13,825 you can use it in one of the same way 178 00:09:13,825 --> 00:09:17,350 and you don't have to check if it's now stored as a string 179 00:09:17,350 --> 00:09:19,133 or as a nested object. 180 00:09:20,270 --> 00:09:22,190 But here, I'll go for the nested object, 181 00:09:22,190 --> 00:09:25,940 simply to, again, practice this nesting aspect 182 00:09:25,940 --> 00:09:28,040 and then separated by a comma, 183 00:09:28,040 --> 00:09:30,610 we can add the next field. 184 00:09:30,610 --> 00:09:32,250 And that could be the rating, 185 00:09:32,250 --> 00:09:34,360 which should be a number between one and five 186 00:09:34,360 --> 00:09:36,730 and let's say, here, it's a three. 187 00:09:36,730 --> 00:09:40,980 Again here, I'm entering this on my own through this shell. 188 00:09:40,980 --> 00:09:44,010 In reality, this would probably be coming 189 00:09:44,010 --> 00:09:46,910 from some application and in that application, 190 00:09:46,910 --> 00:09:49,430 you could make sure that no other values 191 00:09:49,430 --> 00:09:51,933 than one and five are inserted. 192 00:09:53,850 --> 00:09:56,490 Now we also wanna have the text. 193 00:09:56,490 --> 00:09:58,140 Again, please note the line break. 194 00:09:58,140 --> 00:10:01,450 It's text here as a key name. 195 00:10:01,450 --> 00:10:04,143 And the text then, in my case here would be a string. 196 00:10:05,010 --> 00:10:07,150 Unlike in SQL, there is no difference 197 00:10:07,150 --> 00:10:09,320 between a short or a long string, 198 00:10:09,320 --> 00:10:10,460 you can simply store 199 00:10:10,460 --> 00:10:12,913 as much text here as you want in the end. 200 00:10:13,800 --> 00:10:17,063 So here I'll add, this was okay, 201 00:10:18,710 --> 00:10:22,513 could be better, as a text. 202 00:10:23,820 --> 00:10:25,090 Because as a good German, 203 00:10:25,090 --> 00:10:28,313 I of course always have something to criticize, right? 204 00:10:29,500 --> 00:10:33,600 So, next key value pair would be the date. 205 00:10:33,600 --> 00:10:35,370 Now we haven't done this before, 206 00:10:35,370 --> 00:10:38,260 so that might've been something you struggled with 207 00:10:38,260 --> 00:10:41,270 but if you ran a search for MongoDB date, 208 00:10:41,270 --> 00:10:44,253 you'll find the official documentation article here. 209 00:10:45,520 --> 00:10:46,830 And in there, you learn 210 00:10:46,830 --> 00:10:48,290 that you would then create a date 211 00:10:48,290 --> 00:10:51,370 just as you do it in JavaScript. 212 00:10:51,370 --> 00:10:54,490 And you can, for example, pass a date in this format 213 00:10:54,490 --> 00:10:56,840 to this new date function 214 00:10:56,840 --> 00:11:00,540 to define a specific year, month and day, 215 00:11:00,540 --> 00:11:03,440 or even add hours, minutes and seconds, 216 00:11:03,440 --> 00:11:04,993 depending on what you wanna do. 217 00:11:06,220 --> 00:11:08,920 Now here, I don't care about the hours, minutes and seconds, 218 00:11:08,920 --> 00:11:11,530 I just wanna point at a specific date. 219 00:11:11,530 --> 00:11:14,260 And hence here, I'll run new date 220 00:11:14,260 --> 00:11:16,220 and to new date I'll then pass 221 00:11:16,220 --> 00:11:21,220 2021-09-10, for example. 222 00:11:22,870 --> 00:11:24,913 So that would be the date I wanna store. 223 00:11:26,310 --> 00:11:27,350 Last but not least, 224 00:11:27,350 --> 00:11:29,400 we wanna store data about the restaurant 225 00:11:29,400 --> 00:11:31,790 to which this review is linked. 226 00:11:31,790 --> 00:11:33,870 For this, I'll add a restaurant key 227 00:11:33,870 --> 00:11:38,870 and that again is a nested object where I store the ID 228 00:11:38,890 --> 00:11:41,140 of the related restaurant, 229 00:11:41,140 --> 00:11:44,160 could also be named restaurant ID, of course, 230 00:11:44,160 --> 00:11:46,533 or just ID, it's up to you. 231 00:11:47,640 --> 00:11:50,540 And I'll create such an object ID here 232 00:11:50,540 --> 00:11:53,530 and then grab this ID of this restaurant 233 00:11:53,530 --> 00:11:55,460 for which I wanna create a review here 234 00:11:56,880 --> 00:12:01,880 and paste in the quoted ID between object ID. 235 00:12:01,990 --> 00:12:04,730 And then after this object ID value, 236 00:12:04,730 --> 00:12:06,810 I'll add a number of key value pair 237 00:12:06,810 --> 00:12:09,100 and that could be the name of the restaurant, 238 00:12:09,100 --> 00:12:12,170 again, so that we don't have to separately fetch this 239 00:12:12,170 --> 00:12:14,480 if we wanna have a list of all the reviews 240 00:12:14,480 --> 00:12:16,603 with the restaurant names included. 241 00:12:17,830 --> 00:12:22,830 So I'll just paste this in here as well and then hit Enter. 242 00:12:23,140 --> 00:12:27,890 Now this was inserted and therefore, now again, 243 00:12:27,890 --> 00:12:32,593 if we run reviews.find, we see our review document here. 244 00:12:33,510 --> 00:12:35,750 Now of course you can play around with that 245 00:12:35,750 --> 00:12:37,160 and insert more data. 246 00:12:37,160 --> 00:12:40,900 And indeed, I would strongly recommend that you do so. 247 00:12:40,900 --> 00:12:43,040 All the practice querying data, 248 00:12:43,040 --> 00:12:44,950 filter for certain conditions 249 00:12:44,950 --> 00:12:48,010 and then all the practice update and deleting data, 250 00:12:48,010 --> 00:12:50,520 we'll do that together in the next lecture. 251 00:12:50,520 --> 00:12:53,500 So practice the things we did learn up to this point 252 00:12:53,500 --> 00:12:55,890 before we then wrap up this section 253 00:12:55,890 --> 00:12:59,993 to then use MongoDB with node JS in the next section.