Power Query Edit window VERRRRY slow

Hi all. The power query edit window seems to be recalculating the entire file, even though I'm editing a last step (changing the title of a step). I can't stop it. So slow that I should go for lunch. I know that changing the title breaks the reference in subsequent steps, but I'm expecting to see an error in the next step that i fix by renaming the reference, which has worked in the past. The query has maybe seven steps and the data set is very small. Why and what can I do?

Try hitting the escape key, setting calculations to manual, cancelling autosave (if on OneDrive) or changing the refresh settings on the query from automatic to manual (or, indeed, a mixture of these).

Unfortunately, that's the way Power Query works. I'm not sure why renaming a step forces a re-calculation, but it's always done that and there is no way to stop it. It is something that has been brought up to the Power Query team, but I don't think it's come high enough on the radar to be fixed when compared to other bug fixes and feature development.

Personally, if I'm going to do what you're doing, I'd actually pop into the M code (View -> Advanced Editor) and make the edits there. That way there is only one refresh of the preview when you're done, not two (one for the rename, then another when you fix the subsequent steps.) Having said that... editing raw M code is not for the feint of heart...

Oh, and regarding speed of the query overall... there are a LOT of things that can impact the speed. The amount of data, the type of step being performed, the data source (folder vs database). Even for small data sets, depending on what you're doing, it can eat up resources.

If you'd like to go to Power Query -> View -> Advanced Editor and paste that code here, we may be able to point out what may be causing the slowdown. Having said that, it may not be specifically about this query, but may be related to a precedent query as well, should you be creating a query chain to get your results.