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Strong and Weak Power BI Relationships

Alberto Ferrari takes us through the two different kinds of relationships in Power BI:

A relationship in a Tabular model can be strong or weak. In a strong relationship the engine knows that the one-side of the relationship contains unique values. If the engine cannot ensure that the one-side of the relationship contains unique values for the key, then the relationship is weak. A relationship can be weak because either the engine cannot ensure the uniqueness of the constraint – due to technical reasons we outline later – or the developer defined it as such. A weak relationship is not used as part of table expansion. Let us elaborate on this

Something I’d like to see improved in Power BI is to differentiate strong versus weak relationships in the UI. Having no way to differentiate is okay if you only have a few tables or if you designed everything, but coming in late and reviewing a big model, it’s annoying to double-click each link to see if it’s strong or weak.