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All right.

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I mentioned I wanted to get us to writing some code as soon as possible.

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So that's what we're going to do in this video.

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Obviously, it's super early on in the course, so don't get your hopes up for doing anything crazy.

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Impressive.

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It's going to be pretty basic.

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But the idea is that I just want to introduce you to writing some SQL, show you what it's like.

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So the first thing you'll need to do is click on this link if you want to open the slides.

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I've included them with this lecture or I've included the link itself as a resource with this lecture.

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So however you would like to get there, go to this link which takes us to this page right here.

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This is the Try SQL editor and I'm going to make my screen a little bit bigger just so that you can

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see it.

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Here we go.

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And I'll start by just deleting what's already in there.

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So you might be wondering what is this place?

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That's a good question.

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It's an interactive, browser based SQL environment.

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And what that really means is that think of it as your own personal SQL sandbox in the browser, where

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you can go try some things out and play around.

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It's purely for educational purposes.

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So this is not what you would be doing if you were actually working with a real production database.

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But what it lets you do is type some SQL queries and run them by clicking this run SQL button and you'll

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get a result.

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And that's fundamentally the process of working with SQL.

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You type something and then you run it and then you get something back.

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Oh, and before we go any further, I should point out that we're talking about SQL here, not my SQL

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yet.

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And if you're confused about that distinction, totally normal question to have, wait until the next

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section when I go into detail about the differences.

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But for now, I'd like you to try running some code.

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So here's the first line of SQL that we can try running select star from customers.

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So you can either type this or copy it from the slides or from the included code file after this lecture.

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So I'll just copy it from the slides here.

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And then back in the editor, I'll paste it in and click Run.

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So the first thing you'll notice is that we get a bunch of data back.

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So I'm not going to go into the details of the syntax and what all of this means for every command we

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run.

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It's really more about just giving you an experience of running commands.

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The rest of the course talks about the details and the syntax, but what this does is it gives us all

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of the data about customers in this database.

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So you can see we've got 91 customers and every customer here has a name.

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So these are stores or restaurants.

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There's the contact at the restaurant or at the business, the address, the city, the postal code

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and the country.

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So that's all I'll say about that select start from customers.

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That gives us all of our customers data that are in the database right now.

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So here's another thing we could try.

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It's very similar select star from orders.

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So we'll just copy that and back here and the editor, I'll paste it in and click Run SQL, Run SQL.

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Same thing happens, but this time we get all of our data printed out for our orders.

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So you might be wondering where is this data coming from in the first place?

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Very good question.

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It's preprogrammed in here.

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So every time you open this in your browser, you have this pre loaded data set that you can work with.

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And just by taking a quick look at our order data, you can see we have things that can order ID, a

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customer ID, an employee ID and order date and a shipper ID, but there's really not much descriptive

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information here, and that's actually why I chose this table.

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I wanted to make the point that a lot of the data you'll be working with on its own, or like a snapshot

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like this, isn't very meaningful.

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What we actually want to do is start combining it with other tables.

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So we're not going to do that now, but that's what we're building up towards the end of the course

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is how do I combine customers with orders and products and shippers to get some meaningful answers out

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of my data?

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So here's another thing we can do very similar to what we've done already, but there's a little bit

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extra.

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So select start from products order by price descending DSC and if I paste that in here and click Run,

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what I get now are all of the products in my database.

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So they have a product ID, a name, a supplier ID, category ID, a unit and then a price.

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And they're currently sorted by most expensive down to the cheapest all the way at the end.

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So I won't force you to listen to me trying to pronounce some of these, but these are our products

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and they're currently sorted by price.

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So just a simple modification to the query yields radically different results.

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And if we just get rid of that order by price, we get the same data back.

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But now it's ordered by product ID rather than the price.

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And stepping up in complexity a little bit here, here's another query.

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This one significantly longer, and this one actually involves two different entities.

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So we saw customers, we saw orders separately.

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If you try copying this and pasting it in and you click run, what we actually get here is a list of

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records for a customer and then the number of orders a given customer has placed.

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So remember, this data is stored in two separate places.

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We had the customer's data that had nothing to do with orders, and then we had the orders data and

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all that it contained was customer ID and then we've combined them with this query.

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So do not focus on the syntax.

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Don't panic about that.

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Of course we'll get there.

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We'll talk a lot more about how to structure queries.

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I mean, most of this course is about structuring complex queries.

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In fact, here's a quick preview of some of the things we'll be doing.

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So here's an example of a slightly more complicated query.

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This time we're working with photos and images.

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We're working with users and likes and putting them all together to get some information out.

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And here's another one a little bit crazier where we're working with ratings or reviews and TV shows

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and reviewers.

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So think of like a Netflix or iTunes where you could rent or watch a TV show and then rate it from 1

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to 10 or 0 to 5 or whatever the rating scale is here.

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We're working with that data to figure out who our power users are, who are the most active users,

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who are reviewing the most things.

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So we'll be building up to these sort of queries, and by the end of the course you should be able to

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make sense of this and do a lot more, by the way.

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So that was a taste of SQL.

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Hopefully it didn't taste too bad.

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So in the next section we'll dive into the nitty gritty of what SQL is and how it compares to my SQL.

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We'll get everything installed, and then finally we'll have our first set of exercises.