I have been thinking about writing a post about joins for a long time and the day has finally come. In this post, I am going to introduce the join types. In my upcoming post, we are going to learn how to join tables in DAX and in Power Query. Not to complicate things unnecessarily, I am going to keep definitions as simple as possible and use lots of visuals. Let's start then.
Left Outer Join:
It returns all the rows from the left table and the matched rows from the right table. It's also called left join. If you come up with any of the names, be aware that they are the same thing.
Right Outer Join:
Returns all the rows from the right table and the matched rows from the left table. It's also known as right join.
Full Outer Join:
It returns all the rows from both tables whether they are matched or not. Since it takes all rows, it can return very large result sets.
Inner Join:
This one is also known as Inner Join :) It takes rows that have matching values on both tables.
Left Anti Join:
Returns all the rows from the left table which do not have a match on the right table.
Right Anti Join:
Returns all the rows from the right table which do not have a match on the left table.
There are also other join types but these are the ones available in Power BI. My upcoming post is going to be about how to apply these join types to our tables P.S. For empty rows the assigned data is null.
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