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Let's go back to our flight data, let's quickly find all the flights here,

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this is our flight data

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and now let's say we want to store the status for a flight. For this, I'll  use my flight data and I'll update

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many elements,

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I'll pass an empty document as a filter to target them all

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and then here, we have $set

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and then how we want to change them

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and now let's say we want to add a status field but that status is not something like on time which

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you could use

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but let's say this is another document.

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So here another pair of curly braces,

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so this is now a value we set for status which we add to our flight data.

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And now here you can enter anything which you can have in a document, multiple key value pairs, even

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other nested documents if you want.

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So here we could have a description field which is on time and maybe last updated which is one hour ago,

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if we now hit enter here,

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it updated both documents because we had no filter

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and if I now output my flight data in a pretty way, we see these nested documents here and this is what's

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called embedded document,

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I use nested and embedded interchangeably here.

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So this is an embedded document,

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it's another json document within a wrapping json document.

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We got two documents in the collection and each of these documents has a child document

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and as I said, inside of the status, you could have another nested document.

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So if I would repeat my command here and add another value with maybe details, that could be another

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nested document, so another pair of curly braces, maybe this has a responsible field and there, I put my name

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in there.

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If I now hit enter and I output all the flights again,

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now we see another nested document in there,

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so a nested document or an embedded document in an embedded document in a collection document.

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So these are embedded documents

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and now we also can have arrays of data.

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Let's have a look at that in the next lecture.