>>What is the exact difference between two?
>
>>I do need to set order for SQL-Select using OLD style indexes (IDX). That was discussed recently on UT and Hugo R helped me to understand that. For these tables we're using old style IDX indexes.
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>I think you need to SET INDEX TO to open the .idx so it can be used for Rushmore. I can't prove that at this moment.
>
>I'm pretty sure you don't need SET ORDER.

Let me try without, but I'm not yet sure it's relevant. E.g. with or without order it should still produce the correct result, what do you think? When why I got two wrong invoices listed as mismatch and why I can not reproduce the problem in the command window for the mismatched invoices, but do receive exactly the same two invoices as wrong. I really can not understand what's going on.