Question

Define the following terms: entity, attribute, attribute value, relationship instance, composite attribute, multivalued attribute, derived attribute, complex attribute, key attribute, value set (domain).

Short answer

An 'entity' is an object distinguishable from others, and 'attribute' is a property of the entity. 'Attribute value' is the specific value of the said attribute. 'Relationship' is an interaction between entities, while an 'instance' is an individual occurrence of an entity. 'Composite attribute' can be divided into smaller parts, while 'multivalued attribute' may contain more than one value. 'Derived attribute' is an attribute whose value is calculated from other attributes. A 'complex attribute' is a combination of two or more attributes, and 'key attribute' uniquely identifies an entity. Lastly, 'value set' or 'domain' refers to all permissible values an attribute may have.

Step-by-step solution

Definition of Simple Terms

Define 'entity' as an object or concept in the real world that is distinguishable from others. An 'attribute' is a property or characteristic of an entity that helps to differentiate it from others. An 'attribute value' is the specific value that a particular attribute can have.

Definition of Relationship and Instance

'Relationship' is a significant association or interaction between or among entities. An 'instance' refers to an individual occurrence or object of an entity.

Define Composite, Multivalued, and Derived Attributes

A 'composite attribute' is an attribute that can be divided into smaller parts. A 'multivalued attribute' is one that can contain more than one value for a specified attribute. A 'derived attribute' is an attribute whose value is calculated from other attributes.

Definition of Complex Attribute and Key Attribute

A 'complex attribute', also known as a compound attribute, is a combination of two or more attributes. A 'key attribute' is an attribute that uniquely identifies a particular entity in a given dataset or table.

Explanation of Value Set (Domain)

'Value set' or 'domain' refers to the set of all permissible values that a particular attribute can hold.