I have a field, and it should just contain numbers - however due to the data structure it possible that the field contains text. If so, I want to be able to mark and/or filter these rows.
Use IsNum()/IsText() functions
with isnum(). for example:
load Value, isnum(Value) as IsNum inline [
Just as implanning and aez suggest, you can use IsNum().
However, if you have texts like '3E4', these will be marked as TRUE by IsNum(), since it is a correct scientific numeric format. If you have such texts, it may be better to use
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