I have a query in a child business unit with an action type of 'Append.'
This query contains a
join, and it's targeting one of the Data Extensions referenced in the
join. The query was originally targeting and joining on a Shared Data Extension and I had no issue saving or running the activity.
However, I've since changed the target and joined DE to one contained within the child business unit. When I try to save the query activity after targeting the new data extension, I'm given the error:
Type must be 'Update' or the target data extension 'DE' cannot appear in the query.
Why can I only append a data extension that's also referenced in the query when it's a shared DE?