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Ashutosh Kumar Verma

Ashutosh Kumar Verma

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Hi! This is Ashutosh Kumar Verma. I am a software developer at MindStick Software Pvt Ltd since 2021. I have added some new and interesting features to the MindStick website like a story section, audio section, and merge profile feature on MindStick subdomains, etc. I love coding and I have good knowledge of SQL Database.

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Ashutosh Kumar Verma

Ashutosh Kumar Verma

18-Jul-2024

SQL Server Index

An index in a SQL database is a data structure that improves the speed of data retrieval in a database table at the expense of additional space and reduced performance in write operations

Example-
Suppose you have a table Employee with the columns emp_id, name, age, and department_id. If you frequently search for employees based on their emp_id, creating an index on the emp_id column can greatly speed up those search operas

This SQL statement creates an index named idemployee_id in the emp_id column of the Employee table. 

CREATE INDEX idemployee_id ON Employees(emp_id);


The database engine can use the idemployee_id index to quickly find rows where emp_id is equal to 1001, rather than scanning the entire Employees table sequentially.

SELECT * FROM employees WHERE employee_id = 1001;

 

Also, Read: What are SQL Stored Procedures in the Database?

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