Find attached link on this Topic.What type of joins perform in data blending ?
If both table come from the same database you should go for a "traditional join" don't you use blending with the "limited" capabilities on join-type
Effectively I use Data blending as a workaround to multi-facts tables management.
I didn't want to fusion datasources and wanted to have several unique fact table data source, based on the samed Database, so that Tableau user's could produce easely their reports.
But i have to admit that I need either to fusion the source during the data preparation/data modeling