Normalmente eu não publico links que outros blogs, porém acho que esse post explica muito bem a diferença entre esse métodos. Reproduzo abaixo o e-mail que recebemos de um colega alertando sobre o post.

Just came across this blog post, which is probably one of the most useful/clear/relevant entries about Ax I’ve ever seen. It covers something that everyone keeps getting wrong (me included), and explains it very clearly.

http://kashperuk.blogspot.com/2010/03/tutorial-reread-refresh-research.html

X++ developers seem to be having a lot of trouble with these 4 datasource methods, no matter how senior they are in AX.
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