1 00:00:02,540 --> 00:00:05,130 Let's say we wanna update data, 2 00:00:05,130 --> 00:00:08,700 and for example, on my Munich Schnitzelhouse, 3 00:00:08,700 --> 00:00:12,280 I got a problem in the address, if you remember, 4 00:00:12,280 --> 00:00:15,610 or I included the street number 5 00:00:15,610 --> 00:00:18,830 and the wrong one too in the street 6 00:00:18,830 --> 00:00:22,140 where I do have a separate streetNumber field. 7 00:00:22,140 --> 00:00:25,130 So I might want to update this street field 8 00:00:25,130 --> 00:00:26,650 in the address field 9 00:00:26,650 --> 00:00:30,403 of my Munich Schnitzelhouse restaurant document. 10 00:00:31,570 --> 00:00:36,340 Now to do that, we can again use db and then the collection 11 00:00:36,340 --> 00:00:38,860 that holds the document we want to update, 12 00:00:38,860 --> 00:00:40,770 in my case restaurants, 13 00:00:40,770 --> 00:00:43,773 and then execute the updateOne 14 00:00:44,890 --> 00:00:48,610 or updateMany commands here, 15 00:00:48,610 --> 00:00:51,620 simply depending on whether you want to update one 16 00:00:51,620 --> 00:00:54,460 or multiple documents in one go. 17 00:00:54,460 --> 00:00:56,673 And here, I'll update one document, 18 00:00:56,673 --> 00:01:00,553 but the syntax will be the same for updating many documents. 19 00:01:01,810 --> 00:01:06,810 The first parameter value you should pass to updateOne 20 00:01:06,940 --> 00:01:09,760 is a JavaScript object so to say, 21 00:01:09,760 --> 00:01:12,750 so the curly braces opening and closing, 22 00:01:12,750 --> 00:01:15,930 which identifies the document, 23 00:01:15,930 --> 00:01:16,830 or in the case of updateMany, 24 00:01:16,830 --> 00:01:20,150 the documents that you want to update. 25 00:01:20,150 --> 00:01:22,690 Just as with find and findOne, 26 00:01:22,690 --> 00:01:25,970 here you filter for documents. 27 00:01:25,970 --> 00:01:30,850 And in my case, I actually do want to filter by id here. 28 00:01:30,850 --> 00:01:33,880 So before I execute this, 29 00:01:33,880 --> 00:01:35,550 let me delete this, 30 00:01:35,550 --> 00:01:39,480 I'll actually quickly find all documents, 31 00:01:39,480 --> 00:01:41,750 and then I'll grab this id here, 32 00:01:41,750 --> 00:01:43,633 so the part between the quotes. 33 00:01:44,600 --> 00:01:45,955 We can use this as well. 34 00:01:45,955 --> 00:01:50,955 Also for finding, you can just run db.restaurants.find 35 00:01:53,130 --> 00:01:55,730 and then search for an id. 36 00:01:55,730 --> 00:02:00,250 And here, you just wanna create such an ObjectId value 37 00:02:00,250 --> 00:02:03,440 which is a built-in value type that's created 38 00:02:03,440 --> 00:02:07,870 by executing ObjectId like a function like this, 39 00:02:07,870 --> 00:02:11,340 and then you pass your id between quotes to ObjectId 40 00:02:11,340 --> 00:02:16,340 and this will find you this entry here, this document. 41 00:02:16,498 --> 00:02:20,120 ObjectId is simply a built-in value type. 42 00:02:20,120 --> 00:02:23,410 And this is a creation function for such a value 43 00:02:23,410 --> 00:02:27,943 which is used internally by MongoDB for storing ids. 44 00:02:28,920 --> 00:02:30,510 So that's how we can use the id, 45 00:02:30,510 --> 00:02:33,200 and we can now use this for updating as well. 46 00:02:33,200 --> 00:02:38,200 For this, we run db.restaurants.updateOne in my case here, 47 00:02:38,340 --> 00:02:42,420 and then search for the document with this id 48 00:02:42,420 --> 00:02:45,490 as I just showed it to you, like that. 49 00:02:45,490 --> 00:02:48,120 And then the second parameter value 50 00:02:48,120 --> 00:02:51,380 now defines how you want to update this one, 51 00:02:51,380 --> 00:02:52,940 or with updateMany, 52 00:02:52,940 --> 00:02:55,963 the many documents that might have been identified. 53 00:02:57,090 --> 00:03:01,220 For this, you pass in another JavaScript object, so to say. 54 00:03:01,220 --> 00:03:04,840 Whoops, and now I accidentally pressed enter here. 55 00:03:04,840 --> 00:03:07,870 So now in here, between those curly braces, 56 00:03:07,870 --> 00:03:11,060 you now define how that document should be updated. 57 00:03:11,060 --> 00:03:15,870 And for this, you use a special key that's reserved, 58 00:03:15,870 --> 00:03:17,460 that's understood by MongoDB, 59 00:03:17,460 --> 00:03:19,943 and that's the $set key. 60 00:03:21,210 --> 00:03:24,230 This is not a key name that's up to you. 61 00:03:24,230 --> 00:03:27,500 Instead, that's a special key MongoDB will be looking for, 62 00:03:27,500 --> 00:03:30,210 and that takes another object, 63 00:03:30,210 --> 00:03:33,990 so another pair of curly braces, as a value. 64 00:03:33,990 --> 00:03:36,510 And it's now between those curly braces 65 00:03:36,510 --> 00:03:39,813 where you define the actual updating you want to do. 66 00:03:40,800 --> 00:03:45,590 So here, you can now access the properties to keys 67 00:03:45,590 --> 00:03:47,813 of your document. 68 00:03:49,210 --> 00:03:53,670 For example, if I would want to update the restaurant name, 69 00:03:53,670 --> 00:03:55,350 here we could type name, 70 00:03:55,350 --> 00:03:58,170 since that's the key name that stores the restaurant name, 71 00:03:58,170 --> 00:04:01,407 and then our new value, like, "Some new name." 72 00:04:02,670 --> 00:04:04,740 That's adding a line break again for me here, 73 00:04:04,740 --> 00:04:06,703 but it's still one and the same command. 74 00:04:06,703 --> 00:04:08,600 It just added the line break 75 00:04:08,600 --> 00:04:10,500 because I'm running out of space here. 76 00:04:12,040 --> 00:04:14,850 Now I don't wanna update the name here though, 77 00:04:14,850 --> 00:04:18,110 but the great thing about $set and the update command 78 00:04:18,110 --> 00:04:22,710 is that you can also update nested document values. 79 00:04:22,710 --> 00:04:26,400 Then you just need to describe the path to that value 80 00:04:26,400 --> 00:04:28,330 by using quotes here, 81 00:04:28,330 --> 00:04:31,630 and then here we just want to dive into the address key, 82 00:04:31,630 --> 00:04:34,060 which holds that nested object, 83 00:04:34,060 --> 00:04:38,193 and then there with dot into the street key. 84 00:04:39,620 --> 00:04:41,860 And with that, we're telling MongoDB 85 00:04:41,860 --> 00:04:46,120 that we wanna assign a new value to the street key 86 00:04:46,120 --> 00:04:48,393 in the nested address object. 87 00:04:49,740 --> 00:04:53,120 And then here, we could rename this to Some Street 88 00:04:53,120 --> 00:04:56,280 and change it from Some Street 5, which it was before, 89 00:04:56,280 --> 00:04:57,763 to just Some Street. 90 00:04:59,320 --> 00:05:00,760 And if you now hit enter, 91 00:05:00,760 --> 00:05:03,100 you get this confirmation dialog 92 00:05:03,100 --> 00:05:06,380 where you also see how many documents it found 93 00:05:06,380 --> 00:05:09,310 and how many documents it updated. 94 00:05:09,310 --> 00:05:13,923 And if you now again run db.restaurants find here, 95 00:05:13,923 --> 00:05:16,760 you see that here indeed I messed up 96 00:05:16,760 --> 00:05:18,430 and updated the wrong document, 97 00:05:18,430 --> 00:05:21,740 but still, the update succeeded. 98 00:05:21,740 --> 00:05:24,410 Still, it was a small fail from my side. 99 00:05:24,410 --> 00:05:26,850 I did want to update this document, 100 00:05:26,850 --> 00:05:29,960 so I'll quickly fix this by copying this id 101 00:05:29,960 --> 00:05:32,816 and then replacing the id in the update command 102 00:05:32,816 --> 00:05:35,550 with that new id here. 103 00:05:35,550 --> 00:05:38,470 So I'll erase that and use that. 104 00:05:38,470 --> 00:05:41,083 And now with that, this was updated. 105 00:05:42,580 --> 00:05:47,580 And if I now run db.restaurants.find here, 106 00:05:47,880 --> 00:05:50,890 now that was changed to Some Street. 107 00:05:50,890 --> 00:05:53,300 Now they have the same street because I messed up, 108 00:05:53,300 --> 00:05:55,870 but at least different street numbers. 109 00:05:55,870 --> 00:05:59,623 And that's how you can update one or multiple documents.