Untitled Deck

Question 1

What is a Many-to-Many relationship?

Answer 1

A relationship where many records in one entity are associated with many records in another entity.

Question 2

What is a Many-to-One relationship?

Answer 2

A relationship where many records in one entity are associated with one record in another entity.

Question 3

What is a One-to-One relationship?

Answer 3

A relationship where one record in an entity is associated with only one record in another entity.

Question 4

What is a Star Schema?

Answer 4

A data-modeling technique that organizes data into fact and dimension tables, often used in data warehouses.

Question 5

What does a Fact Table contain?

Answer 5

Contains numeric data (e.g., sales, revenue).

Question 6

What do Dimension Tables contain?

Answer 6

Contain descriptive attributes (e.g., time, geography).

Question 7

What is the relationship between Fact and Dimension Tables?

Answer 7

The fact table is connected to dimension tables in a many-to-one (M:1) relationship.

Question 8

What are the stages of the Systems Development Life Cycle (SDLC)?

Answer 8

Planning, Analysis, Detailed Design, Implementation, Maintenance.

Question 9

What is the first stage of the SDLC?

Answer 9

Planning: Determine the project’s scope and objectives.

Question 10

What is the purpose of the Analysis stage in SDLC?

Answer 10

Define system requirements and identify challenges.

Question 11

What is involved in the Detailed Design stage of SDLC?

Answer 11

Outline system specifications.

Question 12

What happens during the Implementation stage of SDLC?

Answer 12

Code and deploy the system.

Question 13

What is the final stage of SDLC?

Answer 13

Maintenance: Regular updates and bug fixes.

Question 14

What are the stages of the Database Life Cycle (DBLC)?

Answer 14

Initial Study, Database Design, Implementation and Loading, Testing and Evaluation, Operation, Maintenance and Evolution.

Question 15

What is the first stage of the DBLC?

Answer 15

Initial Study: Analyze requirements and constraints.

Question 16

What occurs during the Database Design stage of DBLC?

Answer 16

Develop logical and physical models.

Question 17

What happens in the Implementation and Loading stage of DBLC?

Answer 17

Create database structures and load data.

Question 18

What is the purpose of the Testing and Evaluation stage in DBLC?

Answer 18

Verify functionality and performance.

Question 19

What occurs during the Operation stage of DBLC?

Answer 19

Begin database use and monitor.

Question 20

What is the final stage of DBLC?

Answer 20

Maintenance and Evolution: Regular updates and adjustments.

Question 21

What is Data Mining?

Answer 21

The process of analyzing large datasets to discover patterns and extract meaningful information.

Question 22

What is Predictive Analytics?

Answer 22

Uses data mining, statistics, and machine learning to predict future outcomes.

Question 23

What is a Data Warehouse?

Answer 23

A central repository for integrated, subject-oriented, time-variant, and nonvolatile data supporting decision-making.

Question 24

What is a Data Mart?

Answer 24

A smaller, focused subset of a data warehouse for specific business units.

Question 25

What does ETL stand for?

Answer 25

Extract, Transform, Load.

Question 26

What is the Extract phase in ETL?

Answer 26

Retrieve data from various sources.

Question 27

What is the Transform phase in ETL?

Answer 27

Clean and format data.

Question 28

What is the Load phase in ETL?

Answer 28

Store data in a target database.

Question 29

What are ETL Tools?

Answer 29

Software that automates the ETL process (e.g., Informatica, Talend).

Question 30

What are the 3 V's of Big Data?

Answer 30

Volume, Velocity, Variety.

Question 31

What is a Primary Key?

Answer 31

Uniquely identifies a row in a table.

Question 32

What is a Foreign Key?

Answer 32

A primary key from another table, establishing a relationship.

Question 33

What is a Candidate Key?

Answer 33

Any attribute or combination of attributes that can serve as a primary key.

Question 34

What is the syntax for an Insert Statement in SQL?

Answer 34

INSERT INTO table_name (columns) VALUES (values).

Question 35

What is the syntax for a Delete Statement in SQL?

Answer 35

DELETE FROM table_name WHERE condition.

Question 36

What does Truncate do in SQL?

Answer 36

Deletes all rows but keeps the table structure.

Question 37

What does Drop do in SQL?

Answer 37

Deletes the entire table structure.

Question 38

What are Aggregate Functions in SQL?

Answer 38

Functions like SUM(column) and COUNT(column) that perform calculations on data.

Question 39

What does GROUP BY do in SQL?

Answer 39

Groups rows that have the same values in specified columns.

Question 40

What is an Inner Join?

Answer 40

Returns rows with matching values in both tables.

Question 41

What is a Left Join?

Answer 41

All rows from the left table and matching rows from the right.

Question 42

What is a Right Join?

Answer 42

All rows from the right table and matching rows from the left.

Question 43

What is an Outer Join?

Answer 43

Includes matched and unmatched rows from both tables.

Question 44

What is a Surrogate Key?

Answer 44

A system-generated unique key with no intrinsic business meaning.

Question 45

What are NOT NULL constraints?

Answer 45

Disallows null values.

Question 46

What are UNIQUE constraints?

Answer 46

Ensures all values in a column are unique.

Question 47

What are CHECK constraints?

Answer 47

Validates attribute values.

Question 48

What are Optional Relationships in ERD?

Answer 48

A relationship where an entity instance can exist without being related to another entity.

Question 49

What are Mandatory Relationships in ERD?

Answer 49

An entity instance must have a corresponding instance in a related entity.

Question 50

What is DDL?

Answer 50

Data Definition Language: Commands like CREATE, ALTER, DROP.

Question 51

What is DML?

Answer 51

Data Manipulation Language: Commands like INSERT, UPDATE, DELETE.

Question 52

What does UNION ALL do?

Answer 52

Combines datasets and retains duplicates.

Question 53

What does UNION do?

Answer 53

Combines datasets and removes duplicates.

Question 54

What does INTERSECT do?

Answer 54

Returns only common rows.

Question 55

What does EXCEPT do?

Answer 55

Returns rows in the first dataset but not in the second.

Question 56

What is a Supertype?

Answer 56

A general entity type.

Question 57

What is a Subtype?

Answer 57

A specialized entity inheriting from the supertype.

Question 58

What does Hierarchy support in terms of entities?

Answer 58

Supports attribute inheritance.