Why step order matters in Power Query transformations?

< 1 min read

Step order matters because Power Query applies transformations sequentially, top to bottom.
Earlier steps affect the input for later steps, so changing order can break logic.
In my project, we filtered rows first, then removed duplicates; reversing caused incorrect results.
Data type changes should happen before calculations to avoid errors.
Renaming columns too late can break dependent steps like merges or conditional logic.
Query folding can be lost if non-foldable steps are placed too early.
Reordering steps can optimize performance by reducing data volume early.
Applied Steps pane lets us adjust order without rewriting transformations.
Correct order ensures accurate, efficient, and reliable data processing.
So step order directly impacts correctness and performance of transformations.

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