Databases & SQL

Index

/ˈɪndeks/

Definition

A database structure that speeds up read queries on a column at the cost of extra storage and slightly slower writes.

Example in context

"We added a composite index on (user_id, created_at) — query time dropped from 4 seconds to 12ms."

Related terms

Practice this term

Master Index in context by working through exercises in the Databases & SQL module. You'll see the term used in real engineering scenarios with multiple-choice, fill-in-the-blank, and matching drills.