Glossary term
What is Index? Meaning for developers
In System Design
A structure that makes lookups fast. Example: The index at the back of a textbook.
Learn it properly · System DesignLesson 5: SQL Basics Every System Designer NeedsBefore sharding, replicas or NoSQL, learn to use one relational database well. Tables and keys, the queries you will write every day, indexes and EXPLAIN, the N+1 trap, transactions, and the connection limit that takes databases down.In DSA
The position number of an item in an array or string, starting at 0.
Learn it properly · DSALesson 8: ArraysMany values in one variable, numbered from 0. Reading, updating, looping and the first real interview questions on arrays.