Why are you still copying data when you could share it?

Imagine you have finally brought all important enterprise data together in one place. Your team can access it, run analyses and gain valuable insights. Then another department also wants to work with that data – and suddenly copies, redundancy and inconsistency appear. A vicious circle begins.

Sound familiar? You are not alone. In many organisations copying data is still the default when multiple teams or systems need the same information. There is a better way.

In this article you will learn why external storage combined with modern Business Data Cloud solutions such as Databricks and Unity Catalog is transforming how we work with data. We cover the advantages of zero-copy architecture, typical scenarios and concrete recommendations for your data strategy.

What does external storage mean in the Business Data Cloud?

Before we go deeper, the basics: with external storage in the Business Data Cloud your data stays in a central object store such as AWS S3, Azure Data Lake Storage or Google Cloud Storage. Instead of copying data into different systems, all applications, analytics tools and users access this one source – with appropriate access rights and governance rules.

This contrasts with the traditional approach where data is copied multiple times for different use cases and stored in different formats.

The 6 most important advantages of external storage with Databricks / Unity Catalog

1. Zero-copy architecture saves cost and reduces complexity

With zero-copy architecture your data stays exactly where it is – in external object storage. No redundant copies appear, which not only saves storage cost but also greatly reduces the complexity of your data landscape. Imagine: no conflicting versions, no heavy synchronisation processes, no uncertainty about which source is the “right” one.

2. Multi-instance use enables real collaboration

With external storage, different workspaces, teams or even external partners can access the same data sources – of course with clearly defined access rights. This fosters collaboration and ensures everyone works with the same facts. A sales team in Europe and a marketing team in Asia can access exactly the same customer data without duplicating information.

3. Separating compute and storage offers maximum flexibility

One of the greatest advantages of external storage is separating compute from storage. You can scale compute up or down flexibly based on current need – and pay only for what you actually use.

4. Governance with Unity Catalog brings order and security

Databricks Unity Catalog provides unified descriptions, metadata and fine-grained permissions for your data – regardless of where it is physically stored. This ensures consistency and security even when data sits in different buckets or even different clouds.

5. Open standards and flexibility prevent vendor lock-in

Using open formats such as Delta Lake, Apache Iceberg or Parquet makes your external storage universally usable – also outside Databricks. This prevents vendor lock-in and gives you freedom to adapt or extend your technology stack at any time.

6. Cost optimisation through cheaper storage solutions

Affordable, scalable object stores such as S3 or ADLS replace expensive proprietary databases or HANA storage for “cold data” – data that is not queried constantly. This can lead to significant cost savings.

Challenges and how to master them

Of course every technology brings challenges. Here are the most important aspects to watch when using external storage in the Business Data Cloud:

Complexity in permission management: The more external buckets or containers you use, the more important a clean governance approach becomes. Unity Catalog can help here.

Performance tuning for optimal speed: External storage is usually cheaper but potentially slower than highly optimised internal systems. For compute-intensive scenarios consider caching strategies or optimised partitioning of your data.

Know-how requirements for your team: Teams must understand how to cleanly separate and configure storage, workspace and compute – otherwise security or cost traps can appear.