When to Use an Index for Enum Columns #

Scenarios Where Indexing is Beneficial #

• Large tables: If your model has thousands or millions of records, indexing an enum column reduces query execution time.
• Frequent queries: If you often fetch records based on enum values, indexing helps.
• Filtering in reports or dashboards: When filtering users by status: :active or role: :admin, an index improves performance.

Scenarios Where Indexing Might Not Help #

• Low-cardinality columns: If your enum has only a few distinct values (e.g., status with 3 options), the database may not benefit much from indexing.
• Write-heavy tables: Indexing speeds up reads but slows down writes (inserts and updates).