Identifying relationships are transformed in the same way as in the UML to SQL transformation, that is, the foreign key of the transformation gets to be included into the primary key of the dependent entity (the one at the multiple end of the relationship). The difference in ER to SQL transformation case is that the ER model eliminates guessing, which relationships are identifying and which ones are not. UML to SQL transformation guesses, which UML associations should be identifying, by using a heuristic method - composition associations are treated as identifying (this heuristic is controlled by the Treat compositions as identifying transformation property). In ER models, identifying relationships are explicitly marked as such, hence there is no need to guess (See Identifying relationships and dependent entities that specifies how identifying relationships is modeled).