Module 7: Databases - Where Business Data Lives

Why does it take some banks three seconds to answer a question that takes other banks three hours?

Every important business question your organization asks is ultimately a database query. The architecture of that database, the model of that data, and the discipline of the team running it determine whether the answer is fast and right, slow and right, fast and wrong, or unavailable. This module is the executive view of databases: enough to read any data architecture proposal critically and ask the right questions.

What you'll learn in this module

• Relational versus document versus key-value versus graph versus vector databases, and what each is and is not good for
• OLTP versus OLAP, why most organizations need both, and the architectures that bridge them (data warehouse, lakehouse, CDC pipelines)
• Consistency, availability, and partition tolerance: what the CAP theorem actually means for the trade-offs your database vendor is asking you to accept
• How to read a database vendor's pricing without being captured by per-core licensing surprises
• Performance, scalability, and operability: indexes, sharding, replicas, the operational disciplines that separate fast databases from slow ones

The complete module gives executives the working model of databases they need to govern data architecture decisions without delegating them entirely to engineering.