How can we deduplicate a new incremental batch against already committed records in the warehouse?
Performing a left_anti join between incoming batch records and existing warehouse keys discards already-loaded data.
Idempotent batch ETL runs preventing double insertion when pipelines are rerun.
df_new_records = df_incoming.join(df_existing_target, "order_id", "left_anti")Practice typing production-grade PySpark code for Incremental Deduplication against Existing Target Table.