Database Design Best Practices for Developers

Foundation of Applications

Database design has long-lasting implications. Poor decisions early on can haunt you for years. Get it right from the start.

Normalization

Normalize to eliminate redundancy and ensure data integrity. But don't over-normalize—sometimes denormalization improves performance.

Primary Keys

Use surrogate keys (auto-incrementing integers or UUIDs) for primary keys. Natural keys can change and cause problems.

Indexing Strategy

Index columns used in WHERE, JOIN, and ORDER BY clauses. But remember, indexes speed up reads while slowing down writes.

Foreign Keys

Use foreign key constraints to maintain referential integrity. They prevent orphaned records and ensure data consistency.

Naming Conventions

Use clear, consistent names. Plural table names, singular column names. Be consistent with your naming style.

Data Types

Choose appropriate data types. Don't use VARCHAR(255) for everything. Right-sized data types save space and improve performance.

Avoid NULLs

NULL handling is tricky. Use NOT NULL with default values when possible. Be explicit about whether NULLs are allowed.

Audit Fields

Include created_at, updated_at, and soft delete flags. You'll almost always need to track when and why data changed.

Security

Never store sensitive data like passwords in plain text. Use encryption for PII. Implement proper access controls.

Documentation

Document your schema, especially complex relationships and business rules. Future developers will thank you.