2. Clearly describe the five major parts that describes a Database System
3. Discuss the term Encryption and Clearly illustrate its Process
4. Explain the following terms briefly: attribute, domain, entity, relation- ship, entity set,
relationship set, one-to-many relationship, many-to-many relationship, participation constraint,
overlap constraint, covering constraint, weak entity set, aggre- gation.
5. Give at least five functions DBMS
6. Mention at least five disadvantages of DBMS
7. With clear illustration discuss different types of fire walls used in Database security.
8. Clearly explain the building block of a database.
9. With Clear Illustrations, clear roles of participants in a database environment
11. Mention at least 5 levels of Normalization
12. Mention 5 functions of a proxy server
13. With clear illustration show the Information flow in a three-tier architecture.
Answers:
2. Five Major Parts of a Database System:
1. Hardware: This includes the physical devices such as computers, storage systems, and
networks that store and access the data.
2. Software: This includes the software programs that manage the data, including the
database management system (DBMS), operating system, and utilities.
3. Data: This is the actual information stored in the database, such as customer
records, financial transactions, or inventory levels.
4. Procedures: This refers to the rules and instructions for accessing and manipulating the
data, such as security policies and data access controls.
5. People: These are the individuals who use and manage the database, including
database administrators, developers, and end users.
3. Encryption and Its Process:
Encryption is the process of converting data into a secure format to prevent
unauthorized access. The process involves using an algorithm and a key to transform
the original data into ciphertext. The ciphertext can only be decrypted and returned to
its original state using the correct key.
1. Encryption Algorithm: A mathematical formula that performs the encryption. Common
algorithms include AES (Advanced Encryption Standard) and RSA (Rivest–Shamir–
Adleman).
2. Key: A piece of information used by the encryption algorithm. The key is crucial for
decrypting the data. There are symmetric key algorithms (using the same key for
encryption and decryption) and asymmetric key algorithms (using a pair of public and
private keys).
3. Plaintext: The original, unencrypted data.
4. Ciphertext: The result of applying the encryption algorithm to the plaintext using the
key. This is the encrypted data.
4. Brief Explanations of Database Terms:
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Attribute: A characteristic or property of an entity.
Domain: The set of all allowable values for an attribute.
Entity: A real-world object distinguishable from other objects.
Relationship: An association between entities.
Entity Set: A collection of similar entities.
Relationship Set: A collection of similar relationships.
One-to-Many Relationship: A relationship where an entity in one set can be associated
with multiple entities in another set.
Many-to-Many Relationship: A relationship where entities in both sets can be
associated with multiple entities in the other set.
Participation Constraint: Specifies whether each entity in an entity set must participate
in a relationship.
Overlap Constraint: Determines if an entity can participate in multiple subclasses of an
overlapping subtype.
Covering Constraint: Ensures that an entity must belong to at least one subclass of a
covering subtype.
Weak Entity Set: An entity set that doesn't have a primary key attribute on its own.
Aggregation: A higher-level entity composed of related entities.
5. Five Functions of DBMS:
1. Data Definition: Define and manage the structure of the database, including tables,
relationships, and constraints.
2. Data Manipulation: Perform operations on the data, such as inserting, updating, and
deleting records.
3. Data Retrieval: Retrieve data from the database using queries and provide a way for
users to view and analyze data.
4. Security Management: Control access to the database and ensure data integrity and
confidentiality.
5. Data Administration: Manage and monitor the database, including backups,
performance tuning, and user management.
6. Five Disadvantages of DBMS:
1. Cost: Implementing and maintaining a DBMS can be expensive, including software
licensing, hardware, and training costs.
2. Complexity: The complexity of a DBMS can make it challenging to implement and
manage, especially for smaller organizations.
3. Security Concerns: Centralizing data in a database raises security concerns, as
unauthorized access to the database could lead to data breaches.
4. Performance Overhead: Running a DBMS introduces some performance overhead
compared to direct file system access.
5. Vendor Lock-In: Choosing a specific DBMS may lead to dependence on a particular
vendor, limiting flexibility.
7. Types of Firewalls in Database Security:
Firewalls are typically categorized into several types, including:
1. Network Firewalls: Protect the entire network by monitoring and controlling incoming
and outgoing network traffic based on predetermined security rules.
2. Application Layer Firewalls: Operate at the application layer and can understand
specific applications and protocols, providing more granular control.
3. Proxy Firewalls: Act as intermediaries between users and the database, filtering and
forwarding traffic to ensure security.
4. Stateful Inspection Firewalls: Keep track of the state of active connections and make
decisions based on the context of the traffic.
8. Building Blocks of a Database:
The fundamental building blocks of a database include:
1. Tables: Represent entities and their relationships.
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Attributes: Characteristics or properties of entities.
Relationships: Associations between entities.
Keys: Unique identifiers for records in a table.
Constraints: Rules that define the integrity and behavior of the data.
9. Roles of Participants in a Database Environment:
1. Database Administrator (DBA): Manages and oversees the overall database system,
including security, performance, and backups.
2. Database Developer: Designs and implements the database structure, writes queries,
and develops database applications.
3. End Users: Interact with the database to input, retrieve, and analyze data based on their
specific roles.
4. System Administrators: Manage the hardware, network, and system resources
supporting the database.
11. Five Levels of Normalization:
1. First Normal Form (1NF): Eliminate duplicate data by organizing information into
tables.
2. Second Normal Form (2NF): Meet 1NF requirements and remove partial
dependencies.
3. Third Normal Form (3NF): Meet 2NF requirements and eliminate transitive
dependencies.
4. Boyce-Codd Normal Form (BCNF): A more advanced form of 3NF, addressing certain
anomalies.
5. Fourth Normal Form (4NF): Address multi-valued dependencies.
12. Functions of a Proxy Server:
1. Access Control: Controls access to resources and services based on predefined rules.
2. Content Filtering: Filters and blocks content based on specified criteria, enhancing
security and compliance.
3. Anonymity: Acts as an intermediary between users and the internet, providing a level of
anonymity.
4. Caching: Stores copies of frequently accessed content, reducing latency and improving
performance.
5. Load Balancing: Distributes incoming network traffic across multiple servers to prevent
overload and improve reliability.
13. Information Flow in a Three-Tier Architecture:
In a three-tier architecture (presentation layer, application layer, and database layer), the
flow of information typically follows these steps:
1. Presentation Layer: User interacts with the user interface to input data or request
information.
2. Application Layer: Processes user requests, performs business logic, and retrieves or
updates data from the database.
3. Database Layer: Manages the storage and retrieval of data, executing queries and
providing responses to the application layer.