You've done a great job in the course so far you've learned everything from how to run database queries, how to build your own set of tables, how to run functions, and so many things related to managing and working with the database. In this section, we're going to get into one of the main reasons why a SQL was even created, and that is how to deal with relational data.

SQL Is a relational database management system. That means that each one of our tables can reference another table. So for example, if you have a social network you can have a user that's connected to a post. So as soon as that post is created, you know which user is managing it and which user created it. That is all possible by creating relational references and mapping one table to another one.

So in this section, we're going to talk about how that works. And we're also going to talk about how you can run queries that connect those tables together. We're going to talk about all the different kinds of joins that are out there. So the main one which is an INNER JOIN then we're going to talk about outer joins.

Which actually have a couple of variations which is the left outer join and the right outer join. We're going to walk through each one of the differences. So that way you can pick which one you need for your specific scenario.