INSY 3304 UPDATED 2026 EXAM SCRIPT QUESTIONS AND
ANSWERS GRADED A+
✔✔Entity Relationship Model - ✔✔A logical representation of the data for an
organization or for a business area, using entities for categories of data and
relationships for associations between entities.
✔✔Advantages and disadvantages of Entity Relationship Model - ✔✔Advantages:
•Visual modeling yields conceptual simplicity
•Visual representation makes it an effective communication tool
•Is integrated with the dominant relational model
Disadvantages:
•Limited constraint representation
•Limited relationship representation
•No data manipulation language
•Loss of information content occurs when attributes are removed from entities to avoid
crowded displays
✔✔Object-Oriented Model - ✔✔an entity-relationship model is based on a perception of
the world as consisting of a collection of basic objects (entities) and relationships among
these objects; is based on a collection of objects
✔✔Advantages and disadvantages of Object-Oriented Model - ✔✔Advantages:
•Semantic content is added
•Visual representation includes semantic content
•Inheritance promotes data integrity
Disadvantages:
•Slow development of standards caused vendors to supply their own enhancements
•Complex navigational system
•Learning curve is steep
•High system overhead slows transactions
✔✔NoSQL - ✔✔Database management systems that handle non-relational data like
documents, increasingly used for maintaining and querying the large amounts of data
from the Internet. Queries can be made using "Not only Structured Query Language."
✔✔Advantages and disadvantages of NoSQL Model - ✔✔Advantages:
•High scalability, availability, and fault tolerance are provided
•Uses low-cost commodity hardware
•Supports Big Data
•Key-value model improves storage efficiency
Disadvantages:
•Complex programming is required
•There is no relationship support
•There is no transaction integrity support
, •In terms of data consistency, it provides an eventually consistent model
✔✔Entity - ✔✔uses graphic representations to model database components
✔✔Attribute - ✔✔describe particular characteristics
✔✔Table - ✔✔is a collection of related data held in a table format within a database. It
consists of columns and rows.
✔✔Row - ✔✔also called a tuple—represents a single, implicitly structured data item in a
table
✔✔Column - ✔✔is a set of data values of a particular type, one value for each row of
the database.
✔✔Attribute domain - ✔✔is a set of values
✔✔Primary Key - ✔✔attribute or combination of attributes that uniquely identifies a row.
- Natural
- Surrogate
- Entity Integrity
✔✔Foreign Key - ✔✔primary key of one table that has been placed into another table to
create a common attribute.
- Referential Integrity
✔✔Super Key - ✔✔key that can uniquely identify any row in the table
✔✔Candidate Key - ✔✔A minimal super key; An attribute, or combination of attributes,
that uniquely identifies a row in a relation.
✔✔Secondary Key - ✔✔Key used strictly for data retrieval purposes
✔✔Union - ✔✔•Combines all rows from two tables, excluding duplicate rows
•Union-compatible: tables share the same number of columns, and their corresponding
columns share compatible domains
✔✔Intersection - ✔✔•Yields only the rows that appear in both tables •Tables must be
union-compatible to yield valid results
✔✔Difference - ✔✔•Yields all rows in one table that are not found in the other table
•Tables must be union-compatible to yield valid results
✔✔Product - ✔✔•Yields all possible pairs of rows from two tables
ANSWERS GRADED A+
✔✔Entity Relationship Model - ✔✔A logical representation of the data for an
organization or for a business area, using entities for categories of data and
relationships for associations between entities.
✔✔Advantages and disadvantages of Entity Relationship Model - ✔✔Advantages:
•Visual modeling yields conceptual simplicity
•Visual representation makes it an effective communication tool
•Is integrated with the dominant relational model
Disadvantages:
•Limited constraint representation
•Limited relationship representation
•No data manipulation language
•Loss of information content occurs when attributes are removed from entities to avoid
crowded displays
✔✔Object-Oriented Model - ✔✔an entity-relationship model is based on a perception of
the world as consisting of a collection of basic objects (entities) and relationships among
these objects; is based on a collection of objects
✔✔Advantages and disadvantages of Object-Oriented Model - ✔✔Advantages:
•Semantic content is added
•Visual representation includes semantic content
•Inheritance promotes data integrity
Disadvantages:
•Slow development of standards caused vendors to supply their own enhancements
•Complex navigational system
•Learning curve is steep
•High system overhead slows transactions
✔✔NoSQL - ✔✔Database management systems that handle non-relational data like
documents, increasingly used for maintaining and querying the large amounts of data
from the Internet. Queries can be made using "Not only Structured Query Language."
✔✔Advantages and disadvantages of NoSQL Model - ✔✔Advantages:
•High scalability, availability, and fault tolerance are provided
•Uses low-cost commodity hardware
•Supports Big Data
•Key-value model improves storage efficiency
Disadvantages:
•Complex programming is required
•There is no relationship support
•There is no transaction integrity support
, •In terms of data consistency, it provides an eventually consistent model
✔✔Entity - ✔✔uses graphic representations to model database components
✔✔Attribute - ✔✔describe particular characteristics
✔✔Table - ✔✔is a collection of related data held in a table format within a database. It
consists of columns and rows.
✔✔Row - ✔✔also called a tuple—represents a single, implicitly structured data item in a
table
✔✔Column - ✔✔is a set of data values of a particular type, one value for each row of
the database.
✔✔Attribute domain - ✔✔is a set of values
✔✔Primary Key - ✔✔attribute or combination of attributes that uniquely identifies a row.
- Natural
- Surrogate
- Entity Integrity
✔✔Foreign Key - ✔✔primary key of one table that has been placed into another table to
create a common attribute.
- Referential Integrity
✔✔Super Key - ✔✔key that can uniquely identify any row in the table
✔✔Candidate Key - ✔✔A minimal super key; An attribute, or combination of attributes,
that uniquely identifies a row in a relation.
✔✔Secondary Key - ✔✔Key used strictly for data retrieval purposes
✔✔Union - ✔✔•Combines all rows from two tables, excluding duplicate rows
•Union-compatible: tables share the same number of columns, and their corresponding
columns share compatible domains
✔✔Intersection - ✔✔•Yields only the rows that appear in both tables •Tables must be
union-compatible to yield valid results
✔✔Difference - ✔✔•Yields all rows in one table that are not found in the other table
•Tables must be union-compatible to yield valid results
✔✔Product - ✔✔•Yields all possible pairs of rows from two tables
