Quote Originally Posted by Spangamamman View Post
Is there a way to explain when it is safe just deleting some errors that occur, like the one you describe ? I guess that comes with experience mostly, right?
I never have a problem deleting an error...
Usually I would click on it and determine (via the error message) why it is an error and then I'll attempt to correct it.
If it is a Changing Data Type error then it can just be deleted.
Usually you will know the context of the error and you can pretty much determine if it could be deleted and recreate the step or if it is a useless error worthy of deletion.
Obviously errors at the end of the query step list can be deleted more liberally than an error at the beginning of the list, since you have many more dependent steps connected to that step. In this case it is better to fix the error than delete the step.

Quote Originally Posted by Spangamamman View Post
...if I perform everything in master data as you suggest, I end up deleting the first five rows in ONE file, but not both.
I must apologise for leading you to think that all my steps were done in the master. Let me clarify:
I imported the folder and chose EDIT
Then I covered the steps to expand the table column to produce the master query
At this point I went back to the Sample Query and expanded the table and removed the top 5 rows and some other minor clean-up
From then onwards, I stayed in the master
So please note that steps to be performed on all the files MUST be done in the Sample Query (as you correctly indicate)
I think I was just trying to over-stress the fact that you had to select the yellow folder at the master query so I lead you to think that all actions were done there.