How do we define a partition-only WindowSpec to calculate departmental totals across all member rows?
Window.partitionBy('department') creates an unordered window across all rows sharing the same department.
Calculating group aggregates and percentage of department total without a GROUP BY shuffle.
from pyspark.sql.window import Window
dept_window = Window.partitionBy("department")Practice typing production-grade PySpark code for Partitioning Data with partitionBy().