Database Indexes — Speed with Trade-offs
Without indexes, databases scan every row to find data. This works for small tables but becomes painfully slow at scale.
Indexes act like a book’s table of contents, allowing databases to locate records quickly. Queries that filter or sort data benefit significantly.
However, indexes are not free. Each index increases storage usage and slows down insert and update operations because indexes must be updated too.
Good indexing is about balance. Index frequently queried columns and avoid indexing everything blindly.
Understanding indexes is crucial for writing performant, scalable applications.