Databricks Cheat Sheet

Unity Catalog names and grants

USE CATALOG prod;
CREATE SCHEMA IF NOT EXISTS prod.sales;
GRANT USE CATALOG ON CATALOG prod TO `analysts`;
GRANT USE SCHEMA  ON SCHEMA prod.sales TO `analysts`;
GRANT SELECT      ON TABLE prod.sales.orders TO `analysts`;
SHOW GRANTS ON TABLE prod.sales.orders;

Delta table operations

CREATE TABLE prod.sales.orders (order_id BIGINT, amount DECIMAL(12,2), order_date DATE);
MERGE INTO prod.sales.orders t USING updates s ON t.order_id = s.order_id
  WHEN MATCHED THEN UPDATE SET *
  WHEN NOT MATCHED THEN INSERT *;
DESCRIBE HISTORY prod.sales.orders;
SELECT * FROM prod.sales.orders VERSION AS OF 12;
OPTIMIZE prod.sales.orders;
VACUUM prod.sales.orders;          -- removes unreferenced files past retention

PySpark against Unity Catalog

df = spark.table("prod.sales.orders")
(df.filter("order_date = '2026-10-01'")
   .write.mode("overwrite")
   .option("replaceWhere", "order_date = '2026-10-01'")
   .saveAsTable("prod.sales.orders_daily"))

replaceWhere overwrites only the matching slice, which keeps daily reloads idempotent.

Medallion layers

Layer	Contents
Bronze	Raw, append-only, with ingestion metadata
Silver	Cleaned, typed, deduplicated
Gold	Business aggregates and models

Jobs and compute

• Production: job compute or serverless jobs, never a shared interactive cluster.
• Pass the processing date as a job parameter; make every task idempotent.
• Enable auto-termination on interactive clusters.
• Run jobs as a service principal with minimal grants.