How can we filter records ensuring that mandatory primary and foreign key columns contain no null values?
Combining isNotNull() predicates across critical business keys guarantees referential integrity at ingestion.
Enforcing required fields before loading data into relational warehouse star schemas.
df_valid_keys = df.filter(col("customer_id").isNotNull() & col("order_id").isNotNull() & col("store_id").isNotNull())Practice typing production-grade PySpark code for Multi-Column Null Validation.