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.

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Database Management Systems Questions

Multiple choice technology platforms and products
  1. Round Robin

  2. Hash Auto Keys

  3. Key range

  4. Pass-through

  5. Database partitioning

Reveal answer Fill a bubble to check yourself
C,D,E Correct answer
Explanation

For Source Qualifier transformations with relational sources, specific partition types are supported. Key range partitioning divides data based on key value ranges. Pass-through partitioning sends rows to partitions without modification. Database partitioning leverages the source database's native partitioning. Round Robin and Hash Auto Keys are NOT valid for relational Source Qualifiers - they're used for other transformation types.

Multiple choice technology testing
  1. Backup

  2. Recovery

  3. Restore

  4. Monitoring

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

Recovery is the service responsible for automatically setting up the system after a crash or incident with minimal data loss. Backup creates copies, Restore brings data back, and Monitoring tracks health, but Recovery specifically addresses the goal of automatic system restoration with minimal data loss after a failure.

Multiple choice technology operating systems
  1. stop slave

  2. service mysql stop

  3. shutdown

  4. service mysql restart

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

The 'STOP SLAVE' command is the correct MySQL statement to stop replication on a slave server. This command halts the replication SQL thread and/or I/O thread without stopping the entire MySQL service. 'service mysql stop' would stop the entire MySQL server, not just replication.

Multiple choice technology mainframe
  1. Integrated Data Management System

  2. Integrala Data Maintenance System

  3. Integrated Data Maintenance System

  4. Integral Data Management System

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

IDMS stands for Integrated Data Management System, which is a network database model originally developed by Cullinane Corporation (later Computer Associates). It was a competitor to IBM's IMS and used hierarchical/network data structures. The other options with 'Integrala' or 'Maintenance' are incorrect.

Multiple choice technology enterprise content management
  1. Should all three tables be consolidated into one?

  2. Should the cardinalities between the tables be reversed?

  3. Are Branch and Employee dimension tables or fact tables?

  4. Is there a direct relationship between Branch and Employee?

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

Before accepting a proposed operational data structure with transitive paths, a modeler must determine whether a direct relationship exists between the tables (such as Branch and Employee), as this determines whether the intermediate join paths accurately represent real-world associations.

Multiple choice technology enterprise content management
  1. OLAP and DMR

  2. Dimensional and DMR

  3. Relational and SAP BW

  4. Relational and Dimensional

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

In Cognos modeling (such as Framework Manager), authors primarily work with two fundamental model types: Relational (representing tables and joins) and Dimensional (representing dimensions, hierarchies, and measures, which includes Dimensionally Modeled Relational (DMR) models).

Multiple choice technology enterprise content management
  1. De-normalized hierarchy of dimension tables and fact tables.

  2. Normalized dimension tables and detailed fact tables.

  3. Normalized dimension tables and summarized fact tables.

  4. De-normalized dimension tables and fact tables.

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

A classic star schema consists of a centralized fact table containing quantitative metrics, surrounded by de-normalized dimension tables that provide descriptive attributes about the business. De-normalizing the dimensions simplifies queries and improves reporting performance.

Multiple choice technology enterprise content management
  1. Bridge

  2. Connection

  3. Parallel relationship

  4. Many-to-many relationship

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

A parallel relationship trap occurs when multiple relationships (paths) exist between the same entities (often representing different contexts, e.g., an order placed by a customer and shipped to a customer). The structure must be examined to determine if the parallel paths are correct or redundant.

Multiple choice technology enterprise content management
  1. Bridge

  2. Connection

  3. Parallel relationship

  4. Many-to-many relationship

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

A parallel relationship trap occurs when multiple entities or dimensions share similar attributes or structures that should be consolidated into a single relationship. This redundancy can lead to inconsistent data and maintenance problems.

Multiple choice technology enterprise content management
  1. It illustrates a parallel relationship.

  2. It should be consolidated into one table.

  3. . It should be examined for a connection trap.

  4. The cardinality between the tables should be reversed.

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

The operational structure (typically representing a fan trap or chasm trap where two one-to-many relationships fan out from a central table) must be analyzed for connection traps. Connection traps occur when a pathway between entities is ambiguous, leading to incorrect assumptions about relationships between end tables.

Multiple choice technology enterprise content management
  1. Union

  2. Normalized

  3. Operational

  4. Star schema

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

A table in a star schema would typically be either a fact table containing measurements and foreign keys to dimensions, or a dimension table containing descriptive attributes. Star schemas organize data into central facts surrounded by descriptive dimensions.

Multiple choice technology enterprise content management
  1. Comprised of normalized dimension and fact tables.

  2. Organizes dimension tables into hierarchies and levels.

  3. Allows "real time" analysis against disparate data sources.

  4. Cardinality between tables is typically configured as inner joins.

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

To answer this question, the user needs to understand what OLAP means and the characteristics of an OLAP data structure.

OLAP stands for Online Analytical Processing. It is a technology used to store and analyze large amounts of data in a multidimensional format. OLAP data structures are designed to support complex queries and analysis of data.

Now, let's go through each option and explain why it is right or wrong:

A. Comprised of normalized dimension and fact tables.

This option is incorrect. While OLAP data structures do use dimension and fact tables, they are not necessarily normalized. In fact, OLAP data structures use denormalized tables to improve performance.

B. Organizes dimension tables into hierarchies and levels.

This option is correct. OLAP data structures are designed to organize dimension tables into hierarchies and levels to enable quick and easy analysis of data.

C. Allows "real time" analysis against disparate data sources.

This option is incorrect. While OLAP data structures are designed to support complex queries and analysis of data, they are not typically used for real-time analysis. OLAP systems are often updated on a regular basis, rather than in real-time, to improve performance.

D. Cardinality between tables is typically configured as inner joins.

This option is incorrect. While inner joins are often used in OLAP data structures, other types of joins can also be used depending on the specific requirements of the system.

Therefore, the correct answer is:

The Answer is: B. Organizes dimension tables into hierarchies and levels.

Multiple choice technology databases
  1. The SQL*Plus Keyword.

  2. The username

  3. The password

  4. The database name

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

When connecting to Oracle via SQL*Plus, you must specify the SQL*Plus keyword (command), username, and password. The database name is optional if connecting to a default database or using other connection methods. Options A, B, and C are all required components.