Understanding Oracle Constraints: Beginner-Level Quiz

Oracle Constraints Quiz

Welcome to the "Oracle Constraints" quiz! This quiz is designed to test your knowledge of the various types of constraints in Oracle Database, including primary keys, foreign keys, unique constraints, and check constraints. You'll explore how these constraints enforce data integrity and relationships within your database. Whether you're preparing for an interview or looking to solidify your understanding, this quiz will help you assess your grasp of essential concepts in database management. Let’s get started!

1 / 20

NULL means _______?

Empty

ZERO

-1

2 / 20

What is TRUE about NOT NULL Constraint?

By applying the NOT NULL constraint, we will always ensure that the column contains a unique value and won't allow nulls.

When a table's column is declared as NOT NULL, no record in the table can have an empty value for that column.

The value will first be checked for certain conditions before inserting it into the column when a NOT NULL constraint applies to a column in the table.

In columns that are subject to the NOT NULL constraint, duplicate values are not allowed.

3 / 20

Which constraint can be define only at the column level?

Unique

Primary key

Not null

Check

4 / 20

When a table's column is declared as NOT NULL, no record in the table can have an empty value for that column. True or False?

True

False

5 / 20

An entity in A is associated with at most one entity in B. An entity in B, however, can be associated with any number (zero or more) of entities in A.

One-to-many

Many-to-one

One-to-one

Many-to-many

6 / 20

An entity in A is associated with at most one entity in B, and an entity in B is associated with at most one entity in A. This is called as;

Many-to-one

One-to-many

Many-to-many

One-to-one

7 / 20

Constraints are not specified to restrict entries in the relation. True or False?

True

False

8 / 20

Which of the following is/are type of SQL Constraint?

Table Level

Column Level

Both A and B

None of the above

9 / 20

________ is preferred method for enforcing data integrity.

Cursors

Constraints

Triggers

Stored Procedure

10 / 20

Primary key constraint can contain null value, But Unique key constraints should be not null. True or False?

True

False

11 / 20

Select the correct constraint in SQL?

DEFAULT

CHECK

NOT NULL

All of the above

12 / 20

Which of the following is TRUE about UNIQUE constraint?

Unique values will always be present in the column containing the unique constraint.

In columns that are subject to the UNIQUE constraint, duplicate values are not allowed.

A single table can have more than one unique constraint, since it can be applied to more than one column.

All of the above

13 / 20

_______ integrity is achieved by using a foreign key.

Domain Integrity

Entity Integrity

Referential Integrity

User-defined Integrity

14 / 20

Drop Table cannot be used to drop a table referenced by a _________ constraint.

Foreign Key

Local Key

Primary Key

Composite Key

15 / 20

A unique constraint ensures that a column or set of columns in a table contains unique values. True or False?

True

False

16 / 20

__________ express the number of entities to which another entity can be associated via a relationship set.

Relational Cardinality

Mapping Cardinality

Participation Constraints

None of the mentioned

17 / 20

What is TRUE about DEFAULT constraint?

An index can be created on the table using the DEFAULT constraint.

In the event of a DEFAULT constraint being applied to a table's column without a user specifying the value to be inserted when that constraint was applied, the default value that was specified when the constraint was applied will be put into that column.

The value will first be checked for certain conditions before inserting it into the column when a DEFAULT constraint applies to a column in the table.

None of the above

18 / 20

Data integrity constraints are used to:

Improve the quality of data entered for a specific property

Ensure that duplicate records are not entered into the table

Prevent users from changing the values stored in the table

Control who is allowed access to the data

19 / 20

Which of the following can be addressed by enforcing a referential integrity constraint?

Certain fields are required (such as the email address, or phone number) before the record is accepted

Information on the customer must be known before anything can be sold to that customer

All phone numbers must include the area code

Then entering an order quantity, the user must input a number and not some text (i.e., 12 rather than ‘a dozen’)

20 / 20

In addition to eliminating all ____ integrity constraints, CASCADE CONSTRAINTS will also drop all other constraints.

Sequential

Referential

Relational

Consecutive

Your score is

The average score is 60%

Oracle Constraints entail rules applied to database tables to enforce data integrity and consistency. These include NOT NULL, UNIQUE, PRIMARY KEY, FOREIGN KEY, and CHECK. Constraints are essential for maintaining structured and reliable data within the database.

This quiz is designed to test your foundational understanding of Oracle constraints.

Best of luck!