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PySpark Output Schema
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PySpark Output Schema

HardPython

Problem

Given links to production-level PySpark code (150+ lines, pre-processing and processing), write the schema of the output file from each code and give an example of the schema and data after the code runs.

Asked in the Round 3 stage. For this coding version, represent the pipeline as ordered transformation objects and process rows in memory. Return the final schema and resulting rows.

Function: derive_output(source_schema, rows, operations)

source_schema is a list of {name, type} objects. Supported operations are select, withColumn using multiply, filter using eq or gt, and groupBy using sum or count. Preserve column order.

Constraints

  • 1 <= len(source_schema) <= 50
  • 0 <= len(rows) <= 1000
  • 0 <= len(operations) <= 50
  • Column names referenced by operations exist at that point in the pipeline
  • Each groupBy operation contains exactly one aggregation

Function Signature

def derive_output(source_schema, rows, operations):
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