IKM Data Analysis and Business Intelligence 2

Question 1

Which SQL aggregate function would you use to count the number of non-NULL values in a column?

Accepted Answer

COUNT()

Answer

SUM()

Answer

AVG()

Answer

MAX()

Question 2

What is a 'pivot table' used for in data analysis tools like Excel or Power BI?

Accepted Answer

Summarizing and reorganizing data to identify patterns and trends

Answer

Joining two datasets on a common key column

Answer

Encrypting sensitive fields before exporting a report

Answer

Writing back corrected values to the source database

Question 3

Which chart type is most appropriate for showing the distribution of a single continuous variable?

Accepted Answer

Histogram

Answer

Pie chart

Answer

Line chart

Answer

Scatter plot

Question 4

In data analysis, what does the term 'data granularity' refer to?

Accepted Answer

The level of detail or precision at which data is stored or reported

Answer

The speed at which new records are written to the database

Answer

The number of data sources integrated into a single warehouse

Answer

The statistical variance across rows in a numerical column

Question 5

A correlation coefficient of -0.92 between two variables indicates which of the following?

Accepted Answer

A strong negative linear relationship

Answer

No meaningful relationship between the two variables

Answer

A strong positive linear relationship

Answer

A moderate positive linear relationship

Question 6

What is the primary purpose of data profiling in a data quality initiative?

Accepted Answer

Examining data to understand its structure, content, and quality issues

Answer

Encrypting personally identifiable information before analysis

Answer

Compressing large tables to reduce storage costs in the warehouse

Answer

Defining business rules that govern how data should be used

Question 7

Which BI concept refers to pre-computing and storing aggregated query results to speed up report performance?

Accepted Answer

Aggregate caching / materialized views

Answer

Data masking

Answer

Row-level security

Answer

Slowly Changing Dimensions