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Home/Questions/Spark/Big Data/Given a DataFrame with columns id and name, add a new column department: If id < 100 assign HR, if id >= 100 and id < 200 assign admin.

Given a DataFrame with columns id and name, add a new column department: If id < 100 assign HR, if id >= 100 and id < 200 assign admin.

Spark/Big Datahard0.4 min readPremium
Frequency
Low
Asked at 1 company
Category
452
questions in Spark/Big Data
Difficulty Split
88E|81M|283H
in this category
Total Bank
1,863
across 7 categories
Asked at these companies
Dunnhumby
Key Concepts Tested
optimizationpartitionsparksql
Expert AnswerPremium
78 wordsInterview-ready
**Why it matters**: At scale, design choices directly impact reliability, latency, and cost. Wrong decisions compound across jobs and teams. Use when/otherwise: from pyspark.sql.functions import when, col; df.withColumn('department', when(col('id') < 100, 'HR').when((col('id') >= 100) & (col('id') < 200), 'admin').otherwise(None))....
The complete answer continues with detailed implementation patterns, architectural trade-offs, and production-grade considerations. It covers performance optimization strategies, common pitfalls to avoid, and real-world examples from companies like Dunnhumby. The answer also includes follow-up discussion points that interviewers commonly explore.

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