#1
Which of the following is not a type of database management system?
Analytical DBMS
ExplanationAnalytical DBMS is not a type of database management system; other types include relational, NoSQL, and object-oriented DBMS.
#2
Which SQL statement is used to extract data from a database?
SELECT
ExplanationThe SQL statement 'SELECT' is used to extract data from a database; it retrieves data from one or more tables.
#3
What is a primary key?
A key that uniquely identifies each row in a table
ExplanationA primary key is a unique identifier for each row in a table, ensuring data integrity and facilitating relational database structure.
#4
What is the purpose of the SQL 'JOIN' clause?
To combine rows from two or more tables, based on a related column between them
ExplanationThe SQL 'JOIN' clause combines rows from different tables based on a related column, facilitating data retrieval.
#5
What does the term 'OLTP' stand for?
Online Transaction Processing
Explanation'OLTP' stands for Online Transaction Processing, focusing on real-time transactional processing for business applications.
#6
Which of the following is NOT a valid SQL aggregate function?
CREATE
Explanation'CREATE' is not a valid SQL aggregate function; common aggregate functions include COUNT, SUM, AVG, MIN, and MAX.
#7
What does ACID stand for in the context of databases?
Atomicity, Consistency, Isolation, Durability
ExplanationACID stands for Atomicity, Consistency, Isolation, Durability, which are key properties ensuring reliable database transactions.
#8
Which of the following best describes the concept of 'Data Encapsulation' in DBMS?
Combining data and methods into a single unit
ExplanationData Encapsulation in DBMS involves combining data and associated methods into a cohesive unit, enhancing modularity.
#9
Which of the following is not a characteristic of NoSQL databases?
Fixed schema
ExplanationNoSQL databases do not have a fixed schema; they allow flexible and dynamic schema structures.
#10
Which of the following is an example of a Document-Oriented NoSQL database?
MongoDB
ExplanationMongoDB is an example of a Document-Oriented NoSQL database, storing data in flexible, JSON-like documents.
#11
In the context of database indexing, what is a 'B-tree'?
A balanced tree data structure that keeps data sorted and allows searches, sequential access, insertions, and deletions in logarithmic time
ExplanationA 'B-tree' in database indexing is a balanced tree structure that efficiently manages sorted data for searches, access, and modifications.
#12
Which of the following is true about 'Triggers' in a database?
They are special types of stored procedures that are defined to execute automatically in place or after data modifications
ExplanationTriggers in a database are special stored procedures designed to automatically execute in response to specific data modifications, enhancing automation.
#13
In a 'Star Schema' design in data warehousing, what is a fact table?
A table that holds foreign keys from dimension tables as well as measures and facts
ExplanationIn a 'Star Schema' design, a fact table holds foreign keys, measures, and facts, forming the core of a data warehouse.
#14
What is 'Data Mining'?
The process of discovering patterns, correlations, anomalies, and significant relationships in large sets of data
Explanation'Data Mining' is the process of discovering meaningful patterns, correlations, and relationships in large datasets.
#15
What is 'Database Replication'?
The process of copying and distributing data and database objects from one database to another and synchronizing between databases to maintain consistency
Explanation'Database Replication' involves copying and distributing data and objects between databases, ensuring consistency and availability.
#16
Which one of the following is a key feature of 'Column-oriented' DBMS?
Data is stored in columns, making it optimal for reading large volumes of data.
Explanation'Column-oriented' DBMS stores data in columns, optimizing retrieval of large volumes of data.
#17
What is the main advantage of using 'Stored Procedures' in a database?
They enhance security by abstracting the SQL queries from the user and reduce database access by encapsulating complex queries.
Explanation'Stored Procedures' enhance security by abstracting SQL queries, reducing database access and encapsulating complex operations for efficiency.
#18
In the context of database transactions, what does 'Locking' prevent?
Data corruption by ensuring only one transaction can read or write to a piece of data at a time
Explanation'Locking' in database transactions prevents data corruption by ensuring exclusive access, allowing only one transaction to read or write data at a time.
#19
Which of the following best describes 'Entity-Relationship (ER) Models'?
A framework for specifying the logical structure of a database in a graphical form, to represent entities, their attributes, and relationships
Explanation'Entity-Relationship (ER) Models' provide a graphical framework for defining the logical structure of a database, representing entities, attributes, and relationships.
#20
In database systems, what is 'Partitioning' used for?
Dividing a database into multiple pieces to make management, performance tuning, and backup and recovery more efficient
Explanation'Partitioning' in database systems involves dividing a database into smaller parts to enhance management, performance tuning, and backup and recovery efficiency.
#21
What is the primary purpose of 'Normalization' in database design?
To reduce data redundancy and improve data integrity
Explanation'Normalization' in database design aims to reduce data redundancy and enhance data integrity by organizing data into structured and efficient forms.
#22
In database normalization, which normal form is concerned with removing transitive dependency?
Third Normal Form (3NF)
ExplanationThird Normal Form (3NF) in database normalization addresses transitive dependency, enhancing data integrity.
#23
What does the term 'Sharding' refer to in database management?
Breaking a database into smaller, faster, more easily managed parts called shards
ExplanationSharding involves breaking a database into smaller, more manageable parts called shards for improved performance and scalability.
#24
Which one of the following best describes 'CAP Theorem' in distributed database systems?
It states that a distributed computer system cannot simultaneously guarantee consistency, availability, and partition tolerance.
Explanation'CAP Theorem' states the inherent trade-offs in distributed databases, highlighting the challenge of simultaneously ensuring consistency, availability, and partition tolerance.
#25
What is 'Two-phase Commit' protocol in databases?
A synchronization protocol for ensuring that all participants in a distributed transaction either commit or roll back changes
Explanation'Two-phase Commit' is a protocol ensuring synchronization in distributed transactions, requiring all participants to either commit or roll back changes.