Looker Studio Blended Data Joins – Full Outer Join

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Looker Studio Blended Data Joins – Full Outer Join

One of the critical features for data analysts working with complex datasets is the ability to perform various types of joins, including the full outer join. Understanding and utilizing full outer join in Looker Studio can significantly enhance your data analysis capabilities by allowing you to merge data from different sources comprehensively.

In my blog you can find articles about other types of joins, such as Left Outer Join, Right Outer Join and Inner Join.

Full Outer Join

A full outer join is a type of join that returns all records when there is a match in either the left (first) table or the right (second) table. If there is no match, the result will still contain the records from both tables with NULL values in places where the join condition is not met. This join type is particularly useful when you need a complete view of the datasets, including the unmatched rows from both tables.

While an inner join drops any non-matching rows, a full outer join keeps everything, even if they don’t match. In a full outer join, you don’t want to lose any data, and for anything that cannot be matched, a null value will be returned.

google_facebook_ads_blending_gaiile

Here we have 2 tables with Google Ads (left table) and Facebook Ads (right table). We can match the tables based on the Date. There is a match – 6th, 5th and 4th of August. The only differences are August, 9th in the left table, and August, 7th in the right table. 

Consequently, in the final table we are going to have both matching and unmatching rows!

Blended data setup

Creating a blended data source is very easy. 

First of all, you need to name the tables, add dimensions and metrics. There has to be a column in common in both of the tables – here Date.

Then you choose the type of join (Full Outer Join) and set up a join condition – a column in common (Date). And that’s it! Here is what our final table looks like!

full_outer_join_gaille

Summary 

Hope you enjoyed reading the article about Full Outer Join in Looker Studio. If you have any questions about blended data and, particularly, full outer join, I’ll be glad to help you understand!