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Home/Questions/Spark/Big Data/Write a PySpark script to read a CSV file, filter rows where the age column is less than 18, and write the result to a new CSV file.

Write a PySpark script to read a CSV file, filter rows where the age column is less than 18, and write the result to a new CSV file.

Spark/Big Datamedium0.6 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
Freight Tiger
Key Concepts Tested
partitionspark
Expert AnswerPremium
126 wordsInterview-ready
**Why It Matters (Architectural Logic)**: CSV is ubiquitous but inefficient at scale. Filter early; prefer Parquet for production. Handle nulls and type coercion. Read CSV with schema inference or explicit schema: `df = spark.read.option("header", "true").csv("s3://bucket/input.csv")`. Filter: `minors_df = df.filter(F.col("age") < 18)`. If age may be string: `df.filter(F.col("age").cast("int") < 18)`....
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