المشاركة الأصلية كتبت بواسطة hawad

نزل دسكشن بورد من الي حله

1. In relational algebra: is the set difference commutative or not and Why? (1 Mark)
2. What is the difference between multivalued and composite attribute? Explain with Example.

المشاركة الأصلية كتبت بواسطة تقى

q1: In relational algebra: Is the set difference commutative or not and why?

No set difference it's not commutative the result will be different
a difference b is not equal to b difference a in general


q2: What is the difference between multivalued and composite attribute? Explain with example.

Composite attributes: A divided into sub parts . For example, an attribute name could be structured as a composite attribute consisting of first name, middle initial, and last name.

Multivalued attribute: There may be instances where attribute has a set of values for specific entity.
Instructor may have zero, one, or several phone numbers this type of attribute is said to be multivalued.



بالتوفيق