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00:01 The MongoDB shell and native query syntax;
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00:03 we saw that the MongoDB shell which you start by typing the word 'mongo'
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00:07 and it just runs the shell, tries to talk to the local one,
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00:10 there's all the different ways to get it to connect to different servers as we've seen.
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00:13 So once it starts you get this little greater than prompt
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00:16 and you write Javascript so we interact with MongoDB at the lowest level
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00:22 in Javascript in a textual way
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00:24 and actually this is converted to bson a binary extended version of json.
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00:29 So here we type something like db so this is the database we have active
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00:33 and book would be the collection name
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00:35 or table if you're still thinking relationally, but the collection name,
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00:38 and we say things like find or count or sort, or things like this
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00:42 and what we give it is this prototypical json object
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00:45 and what we get back are all the things that match the elements of that prototype.
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00:50 So here you can see we got two records back
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00:53 and they both had the same title as the title we indicated here.
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00:56 So it's very much about passing these prototypical json documents,
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01:00 however sometimes we have to do more than just say
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01:04 I want basically equality in my search,
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01:07 I would like to express things like greater than.
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01:09 So this query here that we have written
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01:12 is actually doing a couple of very interesting things,
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01:14 maybe the thing that stands out the most is this greater than operator,
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01:17 so the dollar gte is indicating, the dollar indicates an operator,
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01:20 and gte is the name the greater than or equal to operator,
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01:23 so instead of just saying ratings.value is nine,
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01:26 we're saying I'd like all the ratings where the value is either equal to or greater than nine.
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01:30 The other powerful and interesting thing here is
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01:33 we're actually traversing this hierarchy of the document
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01:36 we're going to find the ratings array which is a list of subdocuments
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01:39 which has a value as an integer,
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01:41 so we're actually reaching down inside that document
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01:44 and we're doing this query with this operator.
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