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Now there's one last special projection parameter which I want to show you that is related to arrays

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and that is the slice operator

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you could say. Now I'll repeat my query where I look for movies with a rating average greater than nine,

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but now I'll not use $elemMatch your on my genres but I will still use a special value enclosed in

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curly braces.

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I'll look for a slice of the genres array,

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let's say two

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and with this yields to me and for that, I will also add some

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other projection so that I don't get

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everything, I'll also add let's say the name and set it to one because now this will give me a list of items

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where I only have the ID because it's in there by default

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and I didn't exclude it, then I have the name of the series and then I have the genres but only the

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first two elements.

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So all these documents can absolutely have more genres assigned to them but I only see the first two

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because I use slice two and that can be any number,

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you can look for the first three, the first five and you can even use slice in different way.

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You can use it in the array form and then the first element is the amount of elements in the array,

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so in the genres array which you skip

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let's say one and then the second element is the amount of data you want to limit it to, let's say two.

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So now we will pull some items from the genres array but we'll skip the first item and then in this

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case, return the items 2 and 3,

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so the next two items. And now we can see that here we can't directly prove that

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but you could of course search for this element,

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let's maybe do that. Let's search for firefly by ID,

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we see science fiction and western here

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but if we quickly use our movies and we look for ID being equal to our objectId and we print this

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in a pretty format or don't need to do that,

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we can simply project out all the genres,

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so just set genres to one.

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If I now hit enter,

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I get that one entry and we see here, we pulled out science fiction and western,

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actually the genres are adventure, science fiction and western.

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So we skipped the first value and then we output the next two values,

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that is what we did with this syntax, with slice.

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So now you have a lot of different ways of controlling what you see, for normal fields it's straight

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forward with 1 and 0, for arrays, it's hard to do that with 1 and 0 or impossible to be precise,

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so there you got elemMatch, the dollar sign and slice to control which elements of the array end up in

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your result set.

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And with that, you got full control over what you fetch with filtering

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and then which fields of the found documents you include in your result set.