@ארכיטקט עיין בהמשך המקור שציינת:
E. F. Codd used the term "relation" in its mathematical sense of a finitary relation, a set of tuples on some set of n sets S1, S2, .... ,Sn.[4] Thus, an n-ary relation is interpreted, under the Closed-World Assumption, as the extension of some n-adic predicate: all and only those n-tuples whose values, substituted for corresponding free variables in the predicate, yield propositions that hold true, appear in the relation.
Finitary Relation
In mathematics, a finitary relation over sets X1, ..., Xn is a subset of the Cartesian product X1 × ⋯ × Xn; that is, it is a set of n-tuples (x1, ..., xn) consisting of elements xi in Xi.[1][2][3] Typically, the relation describes a possible connection between the elements of an n-tuple. For example, the relation "x is divisible by y and z" consists of the set of 3-tuples such that when substituted to x, y and z, respectively, make the sentence true.
במילים אחרות:
In a relational database, the table is a relation because it stores the relation between data in its column-row format. The columns are the table's attributes, and the rows represent the data records. A single row is known as a tuple
(Definition of Database Relation)
