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In the shell you can run show dbs to see which databases you have on this mongodb server

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and as you can see, as I'm just starting out, I got no databases in there,

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you might even just see admin and config here

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if this is brand new

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but that will be fine too,

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you don't need to create any of these default databases.

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The default databases here simply exist to store configuration for this database server

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or for example the admin database will allow you to create users and roles and how people can use and

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interact with the database,

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all topics we'll cover later in the course.

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So we got no database in here, we can switch to a database with the use command though and you can even

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switch to databases which don't exist yet,

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so for example here I want to start with some flight data, so I'll name it flights and you can choose

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any name you want.

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If you hit enter, you see that we switched to the db flights

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but if I type show dbs, we still don't see that

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even though I did switch to it.

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The reason for this is that this database does not get created before we start entering data in there

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but if we do start entering data, it will be created automatically and implicitly,

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so we don't have to create the database in advance.

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Now as you learned on that slide, we store data in collections, so we don't just need access to that database

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but also to a collection.

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Now we get our flights database and in there, let's say we want to store some flight data.

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You can reference the database you're currently in,

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so in our case the flights database here with db and then you chain commands by typing a dot and then

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the command and one command in quotation marks is that

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we type the name of a collection we want to interact with.

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Let's say we have a flight data collection named like this and this name is also up to you,

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now this is a collection which also doesn't exist yet

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but just like a database, it will be created on demand

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once we start inserting data. Now to insert data, we type another dot

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and now we can type some query commands, commands that allow us to get data out of the collection would

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be higher right now because there is no data in it or commands that allow us to add data and there we

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got the insertOne command for example. As the name suggests, this inserts one document into this collection.

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Now important, make sure you've got the casing and the name in general correct,

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you don't have a typo in there,

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it's one word with a capital O

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and now between these parentheses at the end here, we pass the data we want to store.

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Now a document is always defined with curly braces,

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if you're coming from a javascript world,

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you will know this syntax, there you also create objects with curly braces. To be very precise,

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we're not creating a javascript object here but a json document and json documents are also delimited

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or surrounded by curly braces.

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Now in that document, we now have key value pairs,

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now let's inspect how that looks like and how that works

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before we finally add our data.