Cloud Migration
2024 · 6 months

Cloud Data Warehouse Modernization

Regional Healthcare Analytics Provider

Migrated a decade-old on-premise SQL Server data warehouse to a modern cloud-native architecture, unlocking self-service analytics and cutting infrastructure costs by 60%.

AWS RedshiftAWS GlueS3dbt CloudApache AirflowPythonTerraformSQL Server
The Problem

A regional healthcare analytics company was running critical reporting workloads on aging on-premise SQL Server infrastructure. The system couldn't handle growing data volumes — queries that once ran in minutes were taking hours, and the maintenance burden consumed two full-time engineers. A hardware refresh quote came back at $800K, prompting leadership to explore cloud migration.

Architecture & Strategy

Adopted a phased migration approach using the Strangler Fig pattern, migrating tables and workloads incrementally to eliminate risk while maintaining full business continuity throughout.

  • Conducted a 3-week discovery phase to catalog 400+ tables, identify dependencies, and classify data sensitivity for HIPAA compliance

  • Built AWS Glue ETL pipelines to extract, transform, and load historical data into an S3 data lake with partitioned Parquet format

  • Provisioned Amazon Redshift Serverless as the primary query engine, leveraging automatic scaling for variable analyst workloads

  • Implemented dbt Cloud for all transformation logic, enabling version-controlled, tested SQL with full lineage tracking

  • Ran a 6-week dual-write period validating row counts and aggregate metrics against the legacy system before final cutover

Results
  • Eliminated $800K hardware refresh cost; cloud spend at $12K/month vs. $28K prior operational costs

  • Average query execution time dropped from 4.2 hours to 18 minutes

  • Self-service analytics adoption grew from 6 power users to 40+ analysts within 3 months of go-live

  • Zero data loss or compliance violations during migration of 8 TB of sensitive healthcare data