Architecture Patterns
Data Modeling Basics
Learn how databases are designed so that information stays accurate, fast, and easy to query.
Learning objectives
- Understand tables, rows, and keys
- Explain relationships between entities
- Recognize how structured data is stored and queried
Tables, rows, and keys
Most business systems keep their important data in structured stores. Data is organized into tables - collections of columns (the fields) and rows (individual records). A primary key uniquely identifies each row, so records can be found, updated, and linked reliably.
Relationships
Real systems connect records through relationships. A customer can have many orders; an order belongs to one customer. Modeling these relationships correctly prevents duplicated and contradictory data, and lets different parts of a system share one source of truth.
Good modeling habits
- Remove duplicated data, but don't over-engineer.
- Design access paths around how the data will actually be read and searched.
- Enforce strict validation so bad data cannot enter the system.
Key takeaways
- Data lives in tables linked by keys and relationships.
- Related data is combined at access time along defined relationships.
- Thoughtful modeling keeps data accurate and access fast.