If you’ve used Power Query for any length of time, you almost certainly have joined tables together. Joins are a common operation—and one with various details and options to be explored. Let’s take a few posts to look into some of these interesting areas!

Our focus will be topics specific to how Power Query implements joins, as well as some lesser-known general concepts. We’ll assume that you already have a grasp of commonly-known, non-Power Query specific join basics, like the difference between left, right, inner and full joins. (If such fundamentals are a bit fuzzy, when you bump into a head-scratching part in this series, it might be good to do an online search as a refresher.)

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First up: Power Query’s Two Main Approaches to Performing Joins

Maybe you’ve used query editor to “Merge queries.” Perhaps you’ve hand-crafted the equivalent in M code. In either case, the code that’s created invokes Table.NestedJoin. But nested joins aren’t the only option for joining data in Power Query. The main alternative is the lesser-known Table.Join.

What are some of the differences between these two functions?

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