Computer Knowledge

Database Management Systems

5,543 Questions

Database Management Systems (DBMS) form the core framework for data storage, retrieval, and security in modern software applications. Concepts such as the E-R model, backup planning, SQL integration, and big data architecture are essential for computer knowledge sections. This hub offers a comprehensive set of practice questions to master DBMS fundamentals and advanced database operations.

E-R Model ConceptsBackup and RecoverySQL Server UpgradesJDBC and ODBCBig Data CharacteristicsData VirtualizationOracle Database

Database Management Systems Questions

Multiple choice technology security
  1. Data is validated against a list of values that are known to be valid

  2. Data is validated against a list of values that are known to be invalid

  3. Both of the above

  4. None of the above

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

To solve this question, the user needs to know the definition of "White List" data validation.

Option A is correct. "White List" data validation means that the data is validated against a list of values that are known to be valid. This means that any input that is not on the list of valid values will be rejected or flagged as invalid. It is a way to ensure that only authorized data is accepted.

Option B is incorrect. "Black List" data validation would mean that the data is validated against a list of values that are known to be invalid. In this case, any input that matches a value on the list would be rejected or flagged as invalid.

Option C is incorrect. While both options A and B are described, "White List" data validation refers specifically to option A.

Option D is incorrect. At least one of the options (option A) is correct.

Therefore, the answer is: A. Data is validated against a list of values that are known to be valid.

Multiple choice technology security
  1. Top down

  2. Bottom up

  3. End-to-end

  4. Across the lifecycle of the application

  5. Using a combination of all of the above

Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

The most effective tactical approach for securing database applications is using a combination of all approaches: top-down (policy-driven), bottom-up (secure coding practices), end-to-end (data protection across layers), and across the entire lifecycle (continuous security). A multi-layered defense provides comprehensive protection.

Multiple choice technology databases
  1. a record

  2. a field

  3. a table

  4. an entity

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In strict relational database terminology, an attribute corresponds to a field - a single property or characteristic of an entity (like 'Name' or 'Age' in a Customer table). A record (incorrect Option A) is a row containing all attribute values for one entity. A table (incorrect Option C) is the entire collection of records. An entity (incorrect Option D) is the object being modeled (like Customer), not its individual properties.

Multiple choice technology databases
  1. section name, age

  2. name

  3. undergraduate

  4. name, class name

  5. major, gender

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A junction table resolves a many-to-many relationship (Students to Classes) by combining their primary identifiers. Using 'name' (for student) and 'class name' (for class) creates a composite key. The other choices contain irrelevant attributes like age, or single fields that cannot form a composite key.

Multiple choice technology web technology
  1. Product - Many Manufacturer - Many

  2. Product - Many Manufacturer - One

  3. Product - One Manufacturer - One

  4. Product - One Manufacturer – Many

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The relationship is Many-to-One from Product to Manufacturer. Each Product has exactly one Manufacturer (foreign key Manufacturer_ID in Product table references Manufacturer_ID in Manufacturer table). However, one Manufacturer can produce many Products (multiple Product records can reference the same Manufacturer_ID). This is not Many-to-Many (no junction table), not One-to-One (Manufacturer_ID isn't unique in Product), and not One-to-Many from Product (each Product doesn't have multiple Manufacturers).

Multiple choice technology databases
  1. Design logical data systems

  2. Design physical storage system

  3. Define data entities relevant to the enterprise

  4. All of the above

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Data Architecture's PRIMARY goal is to define data entities relevant to the enterprise - identifying what data exists, its structure, relationships, and meaning. While it may lead to designing logical data systems and physical storage, these are MEANS to an end, not the goal itself. Option D (All of the above) is incorrect because the question asks for the GOAL, not subsequent activities. The goal is semantic - defining data entities - not technical implementation.

Multiple choice technology databases
  1. Business Data Model

  2. Logical Data Model

  3. Data Management Process Model

  4. Data entity/business function Matrix

  5. Data Interface requirements

Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

A data architecture document focuses on high-level data structure, organization, and governance components like business data models, logical data models, data management processes, and entity-function matrices. Data interface requirements are more detailed technical specifications typically addressed during system or physical design phases, making them the correct exclusion from high-level architecture documents.

Multiple choice technology databases
  1. another name for the key linking different tables in a database

  2. another name for a table in an RDBMS

  3. an attribute attached to a record

  4. a row or record in a database table

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

A tuple is the formal database term for a single row or record in a relational database table. Each tuple contains a complete set of attribute values for one entity instance. Options A, B, and C describe other database elements (foreign keys, tables, and attributes respectively).

Multiple choice technology databases
  1. logical model

  2. data flow diagram

  3. entity-relationship diagram

  4. data tree

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

An Entity-Relationship Diagram (ERD) is the standard tool for creating detailed, logical, graphical representations showing entities (objects), their associations (relationships), and the data elements (attributes) that describe them. Logical models focus on structure but may omit graphical representation, data flow diagrams show information movement, and data trees are hierarchical structures not designed for this purpose.

Multiple choice technology databases
  1. computer_id

  2. product_id

  3. company_id

  4. employee_id

  5. order_id

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

In this hierarchical model, Company is the parent entity with three child entities (Employee, Product, Order). Each child entity must reference its parent through a foreign key, which is company_id. Therefore, company_id appears exactly three times in the model - once in each child entity. Other keys like computer_id, employee_id, and order_id are local keys or appear fewer times.

Multiple choice technology databases
  1. A diagram showing the domains of all attributes in the data model

  2. A schedule of data modeling steps

  3. A plan of action for database design

  4. A diagram showing the flow of data in an application

  5. A graphical or language representation of a data model or database

Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

A schema is a formal, graphical, or language-based representation of a database structure or data model defining how data is organized. The other options describe project schedules, design processes, or data flow diagrams, which are not schemas.

Multiple choice technology databases
  1. Entity

  2. Category

  3. Hierarchy

  4. Relationship

  5. Atttibute

Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

In entity-relationship modeling, an attribute is a characteristic or property that describes an entity. Title is a property describing a book, making it an attribute. The book itself would be the entity, genre could be a category, relationships connect entities, and hierarchy refers to structural organization.

Multiple choice technology web technology
  1. Join

  2. View

  3. Field

  4. Table

  5. Tuple

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In database design, an entity represents a real-world object or concept about which data is stored. Entities are implemented as tables in relational databases. The entity's attributes become columns, and individual instances are rows. Options A (Join), B (View), C (Field), and E (Tuple) are other database concepts but not what entities represent.

Multiple choice technology databases
  1. Data about data

  2. Describe a data dictionary

  3. Self-describing

  4. Includes user data

  5. Supports its own structure

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Metadata is defined as 'data about data' - it describes the structure, meaning, and characteristics of data elements. Metadata includes data dictionaries, is self-describing, and supports its own structure. User data (actual business information like customer names or transaction amounts) is NOT metadata - it's the actual data being managed. Options A, B, C, and E all describe characteristics of metadata, while D describes what metadata is not.

Multiple choice technology databases
  1. Logical Data Model

  2. Physical Data Model

  3. Network Data Model

  4. Conceptual Data Model

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The Conceptual Data Model represents the business view of information - it shows what data is important to the business and how it relates, without technical details. Logical models add more structure, physical models include technical implementation, and network models are specific database technologies not business perspectives.