Is the order of applied steps important in power query

Hi!

What considerations are important when you decide in what order you should perform transformation steps in Power Query? Is the engine “smart” so that it can evaluate all steps and decide on the most effective execution or does it simply apply the steps one by one?
Example:
Should you remove unused columns before doing a merge between 2 tables is it not important
Is it better to do filtering as early as possible to reduce the number of rows or is it not important?
Any other considerations that are important?

Thanks
Fredrik

Hi Fredrik,

That’s an excellent question. And you are right the order can matter greatly…

I’ve found some articles by Chris Webb you’ll find interesting. His recommendations, start by removing all unnecessary columns from your tables, especially if you’re doing transformations such as sorts, merges, groupings, pivots or unpivots. And most optimisations the Power Query engine can use only happen on tables – not records or lists – so you should always try to work with tables whenever you can.

Full article and more, start reading here

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