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What is the best way to manage slowly growing data warehouse storage costs?

Stop Paying to Store Data Twice With Delta Lake

Slowly rising storage costs are usually a sign that data is being stored more than once, in a data lake and again in a data warehouse, with a pipeline in between keeping both in sync. Databricks Delta Lake stores data once, in open Parquet format on low-cost object storage, and lets both data engineering and SQL analytics query that same copy directly.

Most organizations get into this position by design, not accident. A data lake handles raw ingestion cheaply, but analysts need warehouse-style performance and ACID guarantees for BI, so a second copy gets built and refreshed on a schedule. Every additional copy adds storage cost, plus the compute cost of the ETL job that keeps it current, plus the operational cost of monitoring that job when it fails. As data volumes grow, all three costs grow with it.

Delta Lake removes the need for the second copy. It adds ACID transactions, schema enforcement, and time travel directly on top of files sitting in object storage, so Databricks SQL can query that data with warehouse-level performance and reliability without a separate loading step. Because storage and compute scale independently and object storage pricing runs well below proprietary warehouse storage, the cost per terabyte drops as volume grows rather than compounding.

Unity Catalog governs that single copy consistently for every workload that touches it, whether it is a SQL query, a machine learning job, or a scheduled report, so consolidating storage does not mean managing separate permission systems.

Key Takeaways

  • Delta Lake stores data once in open Parquet format on object storage, removing the need to maintain a duplicate copy in a separate warehouse.
  • Databricks SQL queries Delta Lake tables directly with warehouse-level performance, so teams get BI-grade speed without an extra ETL step to a second system.
  • Storage and compute scale independently, so growing data volume increases storage cost at object-storage rates rather than proprietary warehouse rates.
  • Unity Catalog governs the single copy of data consistently across SQL, machine learning, and reporting workloads, avoiding duplicate permission management.