1
00:00:02,130 --> 00:00:07,890
Now we're almost done with text indexes, now I want to drop my index again because now I want to show

2
00:00:07,890 --> 00:00:12,450
even more interesting things you can set up when adding the index.

3
00:00:12,480 --> 00:00:19,060
So for that first of all, I need to get the name by getting all indexes,

4
00:00:19,280 --> 00:00:27,830
this is now the name of my text index and now I can drop it by that name by running db products drop index

5
00:00:28,330 --> 00:00:34,790
and then adding that name here, now the index is gone. And I did drop it because I now want to create a new

6
00:00:34,790 --> 00:00:40,050
index with products create index, a new text index of course.

7
00:00:40,040 --> 00:00:49,440
There I want to include my title as a text index and my description as a text index

8
00:00:49,770 --> 00:00:55,140
but now I'll pass some config here because there are two interesting things I can configure about text

9
00:00:55,140 --> 00:00:56,090
indexes.

10
00:00:56,100 --> 00:00:58,230
The first one is the default language,

11
00:00:58,230 --> 00:01:02,370
I can manually assign default language here to a new value.

12
00:01:02,370 --> 00:01:08,480
You saw earlier that the default language it assumed was English and if that is the case,

13
00:01:08,490 --> 00:01:14,820
well you can of course leave that but you could also set this to a different language here and I

14
00:01:14,820 --> 00:01:16,550
could add German here.

15
00:01:16,590 --> 00:01:19,430
Now you're not free to enter whatever you want here,

16
00:01:19,440 --> 00:01:21,400
there is a list of supported languages

17
00:01:21,600 --> 00:01:25,570
and in the last lecture, you find a link to those languages.

18
00:01:26,100 --> 00:01:33,540
Now the field here is not just some cosmetics, we can later use it when searching for text but most importantly

19
00:01:33,540 --> 00:01:38,290
what it will do here is it will define how words are stemmed,

20
00:01:38,520 --> 00:01:46,230
so how prefixes and so on are removed and it will also define what stop words are removed,

21
00:01:46,230 --> 00:01:55,020
so words like is or a are removed in English, in German it would be iste and deya. So the language here

22
00:01:55,530 --> 00:02:01,290
is something you should specify when you know which kind of language or which language will be

23
00:02:01,290 --> 00:02:05,880
stored in your text and you should pretty much know that for any application you're building. Now I'll set

24
00:02:05,880 --> 00:02:11,280
it back to English which is my default and I wouldn't need to specify it here but I'll set it here

25
00:02:11,280 --> 00:02:17,070
explicitly to make it clear that you can set the default language and that this will affect which words

26
00:02:17,280 --> 00:02:20,350
end up in your index.

27
00:02:20,350 --> 00:02:28,810
Now another cool value you can set here is that you can define different weightings for the different

28
00:02:29,500 --> 00:02:31,310
fields you're merging together,

29
00:02:31,540 --> 00:02:34,670
so here I'm merging together title and description.

30
00:02:34,670 --> 00:02:40,420
Now maybe I want to merge them but I want to say yeah, the description should be a higher weight and the

31
00:02:40,420 --> 00:02:46,180
weights will become important when mongodb calculates the score of the result because you might

32
00:02:46,180 --> 00:02:51,590
have awesome in the title but that should not count as much as in the description.

33
00:02:52,030 --> 00:02:56,890
And to set up such weights, we can add a weights key here

34
00:02:58,000 --> 00:03:05,830
in the config object, in the document we pass as a second argument to create index and there, weights

35
00:03:05,890 --> 00:03:08,900
itself holds a document as a value

36
00:03:09,680 --> 00:03:15,560
and in this document, you can now reference your field names like title and simply assign weights that

37
00:03:15,560 --> 00:03:17,210
are relative to each other.

38
00:03:17,270 --> 00:03:25,640
So we could have title 1, description 10 and now description would be worth 10 times as much as title

39
00:03:25,730 --> 00:03:28,870
or would weigh in 10 times as much.

40
00:03:28,880 --> 00:03:37,640
So if I hit enter, we now have this text index created, if I now find all products in my collection here,

41
00:03:37,670 --> 00:03:39,250
you see it looks like this

42
00:03:39,650 --> 00:03:43,580
and now, let's again search with a text index.

43
00:03:43,580 --> 00:03:53,050
So I will use my products to find with $text and now there, we saw the search keyword

44
00:03:53,050 --> 00:03:53,910
already,

45
00:03:53,920 --> 00:03:57,930
now besides the search keyword which I'll fill out in a second,

46
00:03:58,360 --> 00:04:03,820
you can also specify the language, German here.

47
00:04:04,010 --> 00:04:10,220
This is more interesting if you use a different way of storing the language because you can even have

48
00:04:10,220 --> 00:04:13,260
different languages for different documents,

49
00:04:13,280 --> 00:04:17,630
that is an approach which I'll highlight in the last lecture of this module, you'll find the article

50
00:04:17,630 --> 00:04:23,990
there to this advanced set up. Interesting for us here also is that you can also turn on case sensitivity

51
00:04:25,020 --> 00:04:28,710
with case sensitive set to true,

52
00:04:28,710 --> 00:04:31,520
now the default is false, with true

53
00:04:31,530 --> 00:04:34,230
you could suddenly search in a case sensitive way,

54
00:04:34,350 --> 00:04:36,310
so that's just another side note.

55
00:04:36,410 --> 00:04:42,400
Well let's go back to just the text and let's search for red,

56
00:04:42,440 --> 00:04:43,950
now obviously this works,

57
00:04:43,950 --> 00:04:48,250
let's now also add the score here with

58
00:04:48,260 --> 00:04:50,920
$meta text score

59
00:04:51,600 --> 00:04:58,080
and let me also add pretty to make it easier to read and you might not remember the exact number we

60
00:04:58,080 --> 00:05:01,670
had earlier but it was not 6.6666,

61
00:05:01,800 --> 00:05:03,550
it was a different number earlier

62
00:05:03,780 --> 00:05:12,390
and this is because we now added some weights and I can prove this if I simply drop my index,

63
00:05:12,460 --> 00:05:17,620
so first of all I get my indexes to get the name,

64
00:05:17,630 --> 00:05:19,230
here it is,

65
00:05:19,300 --> 00:05:22,360
then I quickly drop the index here

66
00:05:23,500 --> 00:05:24,210
like this

67
00:05:24,400 --> 00:05:27,220
and then I re-add the index with create index

68
00:05:27,250 --> 00:05:33,220
but now without assigning weights, so I will remove that weights assignment here at the end,

69
00:05:33,280 --> 00:05:35,710
I only set the default language which I also could omit,

70
00:05:35,710 --> 00:05:37,420
it doesn't matter.

71
00:05:37,420 --> 00:05:42,700
So now we have a text index working in the same way as the other one but without weights

72
00:05:42,700 --> 00:05:47,820
and now if I execute that same find query, you'll see the score is a different one,

73
00:05:47,860 --> 00:05:54,880
it's not 6.6666 but 1.2 6 because the score is now calculated differently because weights don't

74
00:05:54,880 --> 00:06:00,820
play a role and weights can of course help you well put the weight on the field that holds your most

75
00:06:00,820 --> 00:06:02,980
important key words.

76
00:06:02,980 --> 00:06:05,460
This is the text index, as I mentioned,

77
00:06:05,530 --> 00:06:11,560
you'll find some further articles in the last lecture of this module but the vast majority of important

78
00:06:11,560 --> 00:06:17,860
features were covered here and managing the text index might not be your primary task,

79
00:06:17,950 --> 00:06:23,380
being able to use it with things like the meta score and understanding how it works, that it might

80
00:06:23,380 --> 00:06:28,360
search across multiple fields is definitely something you need to know and hopefully, something which

81
00:06:28,360 --> 00:06:29,150
became clearer

82
00:06:29,160 --> 00:06:29,420
here.