Building MDS Databricks (Modern Data Stacks)

Ibappam discovery team

Building a Modern Data Pipeline with Azure Databricks

This comprehensive guide details the 12 essential steps to construct a scalable, robust, and modern data pipeline using Azure Databricks, organized via the Medallion Architecture. This document is structured and ready to be published as a technical blog post.

Table of Contents

  1. Step 1: Define Pipeline Requirements

  2. Step 2: Configure Cloud Storage

  3. Step 3: Connect Data Sources

  4. Step 4: Establish Data Governance

  5. Step 5: Ingest Data into Bronze

  6. Step 6: Design the Medallion Architecture

  7. Step 7: Manage Incremental Loads

  8. Step 8: Clean Data in Silver

  9. Step 9: Apply Data Quality Rules

  10. Step 10: Build Gold Data Models

  11. Step 11: Serve Data for Analytics

  12. Step 12: Orchestrate and Monitor



Step 1: Define Pipeline Requirements

Description: Identify sources, business goals, refresh needs, security, and expected insights. This foundational step ensures the pipeline meets business objectives by defining exact needs before architectural implementation.

Category

Details

Tools

Azure DevOps, Databricks Workspace

Output

Defined pipeline scope



Step 2: Configure Cloud Storage

Description: Set up Azure Data Lake Storage (ADLS) Gen2 for scalable and centralized data storage. ADLS Gen2 forms the foundation for your data lakehouse, providing highly scalable and secure storage for big data analytics.

Category

Details

Tools

ADLS Gen2

Output

Central storage foundation


Sample Code (Accessing ADLS Gen2 in PySpark):

spark.conf.set(
    "fs.azure.account.key.<storage-account-name>.dfs.core.windows.net",
    "<your-storage-account-key>"
)
# Reading from ADLS Gen2
df = spark.read.csv("abfss://<container-name>@<storage-account-name>.dfs.core.windows.net/path/to/data")



Step 3: Connect Data Sources

Description: Connect databases, APIs, files, SaaS platforms, logs, and streams to bring your varied data into the Azure ecosystem. Effective integration minimizes latency and standardizes ingestion.

Category

Details

Tools

Azure Data Factory, Event Hubs, Lakeflow Connect

Output

Integrated data sources



Step 4: Establish Data Governance

Description: Manage permissions, lineage, metadata, and auditing across data assets to ensure a secure and compliant environment via centralized governance principles.

Category

Details

Tools

Unity Catalog, Azure Key Vault

Output

Secure data environment


Sample Code (Unity Catalog setup via SQL):

CREATE CATALOG IF NOT EXISTS prod_catalog;
USE CATALOG prod_catalog;
CREATE SCHEMA IF NOT EXISTS bronze_schema;
GRANT SELECT ON SCHEMA bronze_schema TO `data_engineers`;



Step 5: Ingest Data into Bronze

Description: Land raw batch and streaming data without major transformations. This provides an auditable history of raw incoming data that acts as the single source of truth for downstream processes.

Category

Details

Tools

Auto Loader, Structured Streaming

Output

Auditable raw data


Sample Code (Using Auto Loader in PySpark):

# Ingest JSON files into Bronze using Auto Loader
bronze_df = (spark.readStream
    .format("cloudFiles")
    .option("cloudFiles.format", "json")
    .option("cloudFiles.schemaLocation", "/checkpoints/schema_bronze")
    .load("abfss://landing@myadls.dfs.core.windows.net/data/"))

(bronze_df.writeStream
    .format("delta")
    .option("checkpointLocation", "/checkpoints/bronze_ingest")
    .trigger(availableNow=True)
    .start("prod_catalog.bronze_schema.raw_table"))



Step 6: Design the Medallion Architecture

Description: Organize data logically into Bronze (raw), Silver (cleansed/filtered), and Gold (business-level aggregates) processing layers to maintain modularity and incremental value.

Category

Details

Tools

Azure Databricks, Delta Lake

Output

Layered pipeline architecture



Step 7: Manage Incremental Loads

Description: Process only new or changed records using checkpoints and Change Data Capture (CDC) to maintain efficient and rapid data ingestion and reduce processing compute costs.

Category

Details

Tools

Delta Lake, Change Data Feed (CDF)

Output

Efficient data ingestion


Sample Code (Enabling and Querying CDF):

-- Enable Change Data Feed on a Delta Table
ALTER TABLE prod_catalog.bronze_schema.raw_table SET TBLPROPERTIES (delta.enableChangeDataFeed = true);

-- Query changes from a specific version
SELECT * FROM table_changes('prod_catalog.bronze_schema.raw_table', 2);



Step 8: Clean Data in Silver

Description: Standardize formats, remove duplicates, and resolve missing or inconsistent values to create a dependable source of truth for exploratory analytics and data science.

Category

Details

Tools

PySpark, SQL, Lakeflow Pipelines

Output

Clean and consistent data


Sample Code (Data Cleaning in PySpark):

from pyspark.sql.functions import col, to_timestamp

silver_df = (spark.read.table("prod_catalog.bronze_schema.raw_table")
    .dropDuplicates(["user_id", "transaction_id"])
    .filter(col("transaction_amount").isNotNull())
    .withColumn("transaction_date", to_timestamp(col("timestamp_str"), "yyyy-MM-dd HH:mm:ss")))

silver_df.write.format("delta").mode("merge").saveAsTable("prod_catalog.silver_schema.cleansed_transactions")



Step 9: Apply Data Quality Rules

Description: Validate accuracy, completeness, uniqueness, and required business conditions so that downstream analytics can trust the datasets implicitly.

Category

Details

Tools

Lakeflow Expectations (Delta Live Tables), PySpark Tests

Output

Trusted datasets


Sample Code (Using Delta Live Tables Expectations):

import dlt

@dlt.table(
  name="trusted_users"
)
@dlt.expect_or_drop("valid_user_id", "user_id IS NOT NULL")
@dlt.expect_or_fail("valid_age", "age > 0 AND age < 120")
def get_trusted_users():
    return spark.readStream.table("prod_catalog.silver_schema.users_silver")



Step 10: Build Gold Data Models

Description: Create dimensions, fact tables, KPIs, aggregates, and business-ready datasets tailored for business intelligence (BI) reporting and executive dashboards.

Category

Details

Tools

Delta Lake, Databricks SQL

Output

Analytics-ready data models


Sample Code (Creating a Gold Aggregation via SQL):

CREATE OR REPLACE TABLE prod_catalog.gold_schema.daily_sales_kpi AS
SELECT
  DATE(transaction_date) AS sales_date,
  store_id,
  SUM(transaction_amount) AS total_revenue,
  COUNT(DISTINCT user_id) AS unique_customers
FROM prod_catalog.silver_schema.cleansed_transactions
GROUP BY sales_date, store_id;



Step 11: Serve Data for Analytics

Description: Expose Gold data to dashboards, applications, machine learning, and AI workloads using efficient serving layers like warehouses and endpoints.

Category

Details

Tools

Databricks SQL Warehouse, Power BI, MLflow

Output

Governed data products



Step 12: Orchestrate and Monitor

Description: Schedule workflows, automate deployments, monitor performance, failures, quality, and costs to ensure a reliable and observable production-ready pipeline.

Category

Details

Tools

Lakeflow Jobs, Asset Bundles, Azure Monitor

Output

Production-ready pipeline


Sample Code (Databricks Asset Bundle YAML snippet for a Job):

resources:
  jobs:
    daily_pipeline_job:
      name: "Daily Medallion Pipeline"
      schedule:
        quartz_cron_expression: "0 0 2 * * ?"
        timezone_id: "UTC"
      tasks:
        - task_key: "ingest_bronze"
          notebook_task:
            notebook_path: "/Workspace/Pipelines/01_bronze_ingest"
        - task_key: "process_silver"
          depends_on:
            - task_key: "ingest_bronze"
          notebook_task:
            notebook_path: "/Workspace/Pipelines/02_silver_transform"



Conclusion: Following these 12 methodical steps ensures your data architecture on Azure Databricks is scalable, strictly governed, and delivers compounding business value consistently.

About the author

Ibappam discovery team
Lost in the echoes of another realm.

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