The relationship set R with descriptive attributes r1, r2, ..., rn, relating entity set A on the 1 end to entity set B on the N end, is normally not converted into a relation of its own. Instead, the relationship is realized by moving the primary key of the relation on the 1 end into the relation on the N end, together with all the attributes of R. In B, the primary key of A, say {a1}, will have to be indicated as foreign key, as it refers to a “foreign” relation. The schema definition would then be
B = ( b1(PK), ..., bn, r1, ..., rn, a1(FK) )
Refer to the Integrity Constraints chapter to see how total participation is realized.