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Now being able to push new values is nice but due to my little example, we now got some duplicate data

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here, hiking and good wine is in there too often. We can of course also pull data from an array,

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so what I can do here is I can again update one document and that will be Maria,

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so name Maria but here, I

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then don't use push

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but pull. Now pull takes an object where I describe how I want to pull or what I want to pull and here

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I can say from the hobbies array,

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I want to pull based on a condition which I then specify here,

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I want to pull every element where the title is equal to hiking

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let's say. With this command, if I now hit enter, you see one document was modified 

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and if I now find all documents, we see Maria has no hiking in there.

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So of course we can now repeat that with good wine to get rid of that too,

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just like this

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and of course you could not just search for equality here, you could use greater than, all these normal

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filter operators you know,

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so now the good wine was also removed from Maria.

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Sometimes you also just want to remove the last element of an array,

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so you have no specific filter criteria, you just want to remove the last element. For that, let's mix

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it up and let's update a document where the name is Chris and for Chris, you see the last element

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is hiking,

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so let's say we want to remove that and we can do that with the

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$pop operator here. You then simply define the name of the field of which you want to pop, hobbies

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for example.

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Now the value here defines if you want to remove the last element, that would be done if you add one

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here

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or if you actually want to pop off the first element which you could do with -1.

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So let's do one, it modified one document

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and if I find all users, you'll see that for Chris,

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indeed there are only two hobbies and hiking which we previously had with a frequency of zero is gone.

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So that is pop which is great if you want to remove the first or last item of an array.