CPS 510 FINAL CERTIFICATION SCRIPT
2026 QUESTIONS WITH SOLUTIONS
GRADED A+
◍ What does ACID stand for?.
Answer: Atomicity, Consistency, Isolation, Durability.
◍ What is the purpose of a NULL?.
Answer: Represents missing or unknown information.
◍ What is the execution order of SELECT clauses?.
Answer: WHERE → GROUP BY → HAVING → ORDER BY.
◍ Why is the relational model significant?.
Answer: Introduced in 1969-70; represents data as tables (relations) with
mathematical foundations.
◍ What is stored in the data dictionary from an ER model?.
Answer: Entity types, relationships, constraints, and specialization
structures.
◍ What are the main features of relational systems?.
Answer: Table-based data view, Logical foundation in math,
Non-pointer-based to users, Uses SQL.
◍ What is a rollback?.
Answer: Undoes transaction changes upon failure.
◍ What is specialization?.
Answer: Dividing an entity into subgroups (subclasses) based on
characteristics.
◍ How does the DBMS relate to users and application programs?.
Answer: Users → Applications → DBMS → Database; DBMS mediates
, between user requests and physical data.
◍ What are the three stages of conceptual schema design?.
Answer: Choice of model (ER diagram), Normalization, Optimization (data
dictionary).
◍ What are referential actions?.
Answer: SET DEFAULT, SET NULL, CASCADE, NO ACTION.
◍ How does a DBMS enforce security?.
Answer: By controlling access: Students see their marks; TAs enter marks
for one assignment; Instructors have full access.
◍ What is the catalog?.
Answer: A set of system relvars containing metadata about tables, views,
indexes, and constraints.
◍ What is logical data independence?.
Answer: Change conceptual schema without affecting external views or
applications.
◍ What are aggregate functions?.
Answer: AVG, MIN, MAX, SUM, COUNT (Oracle adds VARIANCE,
STDDEV).
◍ Who introduced the ER model and when?.
Answer: Peter Chen, 1976.
◍ What is the degree (arity) of a relation?.
Answer: The number of attributes (columns).
◍ What does data integrity mean?.
Answer: Ensuring data correctness and validity — e.g., employees cannot
belong to a non-existent department or have hours = 400.
◍ What does NULL represent?.
Answer: Missing or inapplicable attribute value.
◍ What is the DBMS?.
2026 QUESTIONS WITH SOLUTIONS
GRADED A+
◍ What does ACID stand for?.
Answer: Atomicity, Consistency, Isolation, Durability.
◍ What is the purpose of a NULL?.
Answer: Represents missing or unknown information.
◍ What is the execution order of SELECT clauses?.
Answer: WHERE → GROUP BY → HAVING → ORDER BY.
◍ Why is the relational model significant?.
Answer: Introduced in 1969-70; represents data as tables (relations) with
mathematical foundations.
◍ What is stored in the data dictionary from an ER model?.
Answer: Entity types, relationships, constraints, and specialization
structures.
◍ What are the main features of relational systems?.
Answer: Table-based data view, Logical foundation in math,
Non-pointer-based to users, Uses SQL.
◍ What is a rollback?.
Answer: Undoes transaction changes upon failure.
◍ What is specialization?.
Answer: Dividing an entity into subgroups (subclasses) based on
characteristics.
◍ How does the DBMS relate to users and application programs?.
Answer: Users → Applications → DBMS → Database; DBMS mediates
, between user requests and physical data.
◍ What are the three stages of conceptual schema design?.
Answer: Choice of model (ER diagram), Normalization, Optimization (data
dictionary).
◍ What are referential actions?.
Answer: SET DEFAULT, SET NULL, CASCADE, NO ACTION.
◍ How does a DBMS enforce security?.
Answer: By controlling access: Students see their marks; TAs enter marks
for one assignment; Instructors have full access.
◍ What is the catalog?.
Answer: A set of system relvars containing metadata about tables, views,
indexes, and constraints.
◍ What is logical data independence?.
Answer: Change conceptual schema without affecting external views or
applications.
◍ What are aggregate functions?.
Answer: AVG, MIN, MAX, SUM, COUNT (Oracle adds VARIANCE,
STDDEV).
◍ Who introduced the ER model and when?.
Answer: Peter Chen, 1976.
◍ What is the degree (arity) of a relation?.
Answer: The number of attributes (columns).
◍ What does data integrity mean?.
Answer: Ensuring data correctness and validity — e.g., employees cannot
belong to a non-existent department or have hours = 400.
◍ What does NULL represent?.
Answer: Missing or inapplicable attribute value.
◍ What is the DBMS?.
