Question 4
(a) Explain the following database management terms:
(i) entities;
(ii) attributes;
(iii) relationships.
(b) (i) Define cardinality in database management.
(ii) Mention three cardinality relationships in database management.
Observation
(a) (i) Entities
are objects or items concepts within the database model. They are implemented in a database as tables. Each row of the table represents an instance of the entity.
(ii) Attributes
are the unique distinguishing characteristic/properties of the entity in a database. They are implemented as fields/columns in a table.
(iii) Relationship
is an association/links among the instance of one or more entities in a database.
(b) (i) Cardinality
defines the relationship between the entities/tables in a database.
OR
Cardinality refers to the uniqueness of data values contained in a column.
(ii) Cardinality relationships in database
(A) One-to-one relationship
(B) One-to-many relationship/many-to-one relationship
(C) Many-to-many relationship
The question tested candidates’ knowledge ofdatabase management system terms.
It was reported that candidates’ responses showed poor knowledge of the terms used indatabase management system.