Topic 14718 min readStructured Tutorial
Understanding Clustered Indexes in SQL
Quick Answer
A clustered index in SQL determines the physical order of data in a table based on the indexed column(s). It improves query performance by sorting and storing rows in order, making data retrieval faster for range queries and primary key lookups.
Learning Objectives
- Define what a clustered index is and how it differs from other indexes.
- Explain how clustered indexes affect data storage and retrieval.
- Identify scenarios where clustered indexes improve SQL query performance.
Introduction
Indexes are critical for improving database query performance by allowing faster data retrieval.
Among various types of indexes, the clustered index plays a unique role by defining the physical order of data in a table.
Data is best found when it is well organized.
