Top 10 Data Anayst Quiz

1. What is a primary key in a database?

A unique index for sorting data
A unique identifier for a record
A field that can be left empty
A table used for queries

2. What does SQL stand for?

Structured Query Layout
Structured Query Language
Simple Query Language
Standard Query Layout

3. Which Excel function is used to find the average value in a dataset?

MAX
COUNT
AVERAGE
MIN

4. What is the purpose of a data warehouse?

To store unstructured data
To store large amounts of structured data for analysis
To perform real-time transaction processing
To create visualizations

5. In Python, which library is most commonly used for data manipulation?

NumPy
Pandas
Matplotlib
Seaborn

6. What is a data model in database design?

A framework for visualizing charts
A conceptual framework for how data is stored
A tool for building machine learning models
A type of data visualization

7. What is data normalization?

A process of converting data into graphs
A method of organizing data to reduce redundancy
A way to validate data quality
A technique for summarizing data

8. What does ETL stand for in data processing?

Extract, Transform, Load
Extract, Transfer, Load
Evaluate, Transform, Load
Export, Transform, Load

9. What is the difference between clustered and non-clustered indexes?

Clustered indexes are used for complex queries
Clustered indexes determine physical storage order
Non-clustered indexes are slower
Clustered indexes work only on primary keys

10. How does a LEFT JOIN work in SQL?

Returns only rows where there is a match in both tables
Returns all rows from the left table, with matched rows from the right
Returns only distinct values
Joins data from the first and last rows