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What does "index" mean in programming?
index is one of the most common terms in software development. This guide explains what it means, how it is used in practice, and why it matters, with real examples from the developer world.
Definition
A data structure that improves the speed of data retrieval operations in a database. Indexes trade additional storage space and slower writes for much faster reads on the indexed columns.
Example
"Add an index on the email column to speed up the login query."
Word forms
| Form | Type | Meaning | Example |
|---|---|---|---|
| index | noun | A data structure that speeds up lookups in a database | "Add an index on the email column to speed up login queries." |
| index | verb (infinitive) | To create an index on a database column | "Index the foreign key columns for better join performance." |
| indexed | past tense | Already has an index defined | "The column is indexed so the query runs in milliseconds." |
Related terms
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