How do we compute each employee's salary as a percentage share of their department's total payroll?
Applying sum(salary) over an unordered departmental window and dividing individual salary by the total.
Payroll budget distribution, cost center allocation, and organizational equity benchmarking.
from pyspark.sql.window import Window
from pyspark.sql.functions import col, sum
dept_window = Window.partitionBy("department")
df = df.withColumn("dept_total_salary", sum(col("salary")).over(dept_window)) \
.withColumn("salary_pct_of_dept", col("salary") / col("dept_total_salary"))Practice typing production-grade PySpark code for Partition-Level Aggregate Comparison.