IN UNION Duplicate tuples are allowed.

is a relation that includes all tuples that are in both R and S.

is a relation that includes all tuples that are in R but not in S.

R ∪ S ≠ S ∪ R

R − S ≠ S – R

The set operations ∪ and ∩ are ……………… but “–” is not.

If the cardinality of R, S and R∩S is 40, 50, and 20 respectively, then the cardinality of R∪S is 70.

R ∪ (S ∪ T) = (R ∪ S) ∪ T and (R ∩ S ) ∩ T = R ∩ (S ∩ T )

R ∩ S = ((R ∪ S ) − (R − S )) − (S − R)

For the Cartesian product to be defined, the two relations involved must have disjoint headers—that is, they must not have a common attribute name

CARTESIAN PRODUCT operation applied by itself is generally meaningful .

DIVISION operation is a binary relational operation that divides one set of rows into another set of rows based on specified conditions

DIVISION general form is R÷ S to apply this operation the relation S must be subset of Relation R.

U = R x S then U ÷ S =

U = R x S then U ÷ R =

U = R x S then R ÷ U =

How the tuples in a base relation are stored and updated

How users interpret the relation schemas and the meaning of their attributes

logical level =

physical storage level =