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Now you are also not limited to querying top level fields, if I quickly find one element so that we see

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the structure again. You see in this document,

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we have a lot of embedded documents, externals, image, the network where you could see this,

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the rating which holds one nested field, schedule,

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so we have a bunch of embedded fields here,

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we also have arrays and I'll come back to querying arrays too.

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Now you can query such embedded fields as well and querying them is quite simple,

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I show you the syntax earlier already,

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you can run your find or find one query by passing a document

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and now let's say we want to look for all series or all items here where the rating is greater than

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7,

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so for example, Glee should not be included.

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Now we can do this by specifying the path to the field we're interested in,

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so in our case that's the average yield instead of the rating embedded document. You specify such a path

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by using double quotation marks around the path, this is required because otherwise the dot is considered

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an invalid character and then you have your field that holds the embedded document,

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so in my case that field name is rating, not ratings, rating, that holds the embedded document.

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So rating in my case, dot and then the name of the field

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and if you had multiple levels, let's say there you had the total rating and then you had the average,

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this would work too

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but I just happened to have an average field in there and that holds the value

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I want to query.

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Now we could query for equality

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but as I mentioned, I want to find all ratings greater than 7 and that can be done like this,

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it also doesn't matter if you use 7 or a 7.0 here, you can use both.

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Now if I do that and I have pretty print my results,

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I get back quite a lot of results but you should not find any item where the rating is below 7, that

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should not be the case.

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So there, you find an easy way of querying embedded documents

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and as I mentioned, that embedding, that path can be as deep as you need it to be,

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so you're not limited to one level,

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you can add as many dots in your path as required to dig into that embedded document. And then you can

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use all the queries selectors, all the operators on that embedded field.

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You can also query arrays,

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we got the genres array in our data which has some keywords for the different genres,

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now let's say we want to find all items which have the drama genre.

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Now to make this work, we'll use a find query again but the term here or the query expression of course

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differs.

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Now keep in mind, we're looking for the genres field, that is not an embedded document but an array,

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the approach I show you would work equally for arrays

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in embedded documents, of course you just would need to use the dot notation to reach that array in there

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but then it's just a normal field.

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So here it's a top level field named genres,

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so let's look for genres here

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and then let's try this, let's try looking for drama.

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The casing here is important by the way, drama like this will not give you anything because there is

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no drama, it always starts with a capital D,

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if I look for it like this, I do get back results and all these results will have genres

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that also includes drama and that's the important thing,

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equality here with an array does not mean that drama is the only item in the array, so it's not like

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genres is equal to just drama.

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It's just equal to

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there is drama in the array so this item does exist,

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genres is equal to drama in that drama exists in the array but there may be more genres.

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If you want exact equality, you can get that too of course,

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if you want exact equality, you can modify your query to not look for genres drama like this

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but now you include square brackets around that. That signals mongodb that you will look for genres

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being equal to exactly that array.

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If I now hit enter, I also find some documents and here

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indeed, genres is just drama,

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just an array with drama in there,

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no other genres.

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So this is really important to understand, this is how you can query arrays in its basic form either for

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exact equality or for doesn't include this item,

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both can be helpful depending on what you're trying to achieve.