I want to use FetchXML query to extract data from Dynamics 365 in Azure Data Factory.
I used this initial setup for the entity 'campaignactivity' (without any FetchXML query):

And in preview data I see columns like actualstart:

But when I tried using FetchXML query, I got this error:

This is the FetchXML query I am using:

I tried testing it with only one attribute but I only get the primary key as output:

I tried this pipeline with other entities too. Some of them don't produce any error but it also has fewer columns than not using FetchXML query.
Maybe there's some issue parsing the text you gave. I've got it to work using single quotes or text functions like
@concat().This is a fetch that i use for the contact entity for example:
And here is another without
@concat, make sure to use single quotes:Also, for some reason if you dont specify any attributes, it fetches the whole entity.