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Data Analyst
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Null Handling
Data Analyst
Null Handling questions
8 questions on Null Handling for data analysts, easiest first.
Easy
3
COUNT(*) vs COUNT(column)
easy
Finding NULL values
easy
AVG with a NULL value
easy
Medium
1
SUM over zero matching rows
medium
Hard
4
NOT IN returns nothing
hard
Not-equal filter loses rows
hard
Filtering NaN with == in pandas
hard
GROUP BY with NULL cities
hard
