CS403 Quiz 3 by Bird

Q1. Which of the following is one of the purposes of using DDL commands?

1. creating and destroying databases
2. updating records into databases
3. inserting records into databases
4. manipulating databases

Correct answer: updating records into databases

Q2. Which of the following describe the Degree of a relationships in E-R Data Model?

1. Number of participating entity types
2. Number of participating relations
3. Number of participating constraints
4. Number of participating attribute types

Correct answer: Number of participating entity types

Q3. If A→ B and CB → D, then AC → D. 1. The above rule follows _____________ inference rule.

1. Augmentation
2. Decomposition
3. Pseudo transitivity
4. Additivity

Correct answer: Pseudo transitivity

Q4. In ____________ join, only selected rows of a relation are made cross product with second relation.

1. Semi
2. Outer
3. Theta
4. Normal

Correct answer: Semi

Q5. SQL stand for?

1. Standard query list
2. Structure query language
3. Standard query language
4. Structure query list

Correct answer: Structure query language

Q6. The maximum PL/SQL size of data type “VARCHAR2” in DBMS is _____________ bytes.

1. 28767
2. 42767
3. 32767
4. 52767

Correct answer: 32767

Q7. _____________________ states that in a relation no attribute of a primary key (PK) can have a null value.

1. Null Constraint
2. Domain Constraint
3. Referential Integrity Constraint
4. Entity Integrity Constraint

Correct answer: Entity Integrity Constraint

Q8. Indexes are built on _________to improve query performance.

1. Tables
2. Relationships
3. Columns
4. Records

Correct answer: Columns

Q9. In the relational model, the number of attributes and number of tuples in a relation are termed as __________and ______________respectively.

1. cardinality, degree
2. degree, cardinality
3. domain, degree
4. cardinality, domain

Correct answer: degree, cardinality

Q10. In Relational Data Model, the ________ of a relation is the number of rows in that relation.

1. Domain
2. Constraint
3. Degree
4. Cardinality

Correct answer: Cardinality