When designing a database, developers often encounter a seemingly simple decision: Should we use a boolean or an integer to represent a (decision) field? While the difference might seem trivial at first, the choice can have significant implications for storage, maintainability, and scalability. Let’s explore the pros and cons of each approach, with a focus on storage size, operational overhead, and long-term maintainability.

Booleans: The Simple, Binary Option

Initial Design

A boolean field is ideal when a value can only have two states: true or false. For example, fields like isActive or isAdmin fit perfectly into that. Here’s a typical example: