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SQL SERVER – Example of DISTINCT in Aggregate Functions

Pinal Dave
SQL, SQL Server, SQL Tips and Tricks
2 Comments

Just a day ago, I was was asked this question in one of the teaching session to my team members. One of the member asked me if I can use DISTINCT in Aggregate Function and does it make any difference.

Of course! It does make difference. DISTINCT can be used to return unique rows from a result set and it can be used to force unique column values within an aggregate function.

USE AdventureWorks
GO
SELECT SUM(DISTINCT ReorderPoint) ResultDistinct
FROM Production.Product
GO
SELECT SUM(ReorderPoint) ResultNoDistinct
FROM Production.Product
GO

SQL SERVER - Example of DISTINCT in Aggregate Functions distinctaggregate

Reference : Pinal Dave (https://blog.sqlauthority.com)

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2 Comments. Leave new

  • DBAtor
    July 17, 2008 7:28 pm

    Its very urgent..

    I have a table called Permissions. in that I have iParentID, iPermissionID there….if I give the iParentId=1, suppose this record having the iPermissionId s 6,7,8. I need to display hirarchy wise…

    can anyone help me regarding this

    Reply

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Pinal Dave is an SQL Server Performance Tuning Expert and independent consultant with over 22 years of hands-on experience. He holds a Masters of Science degree and numerous database certifications.

Pinal has authored 14 SQL Server database books and 88 Pluralsight courses. To freely share his knowledge and help others build their expertise, Pinal has also written more than 5,800 database tech articles on his blog at https://blog.sqlauthority.com.

Pinal is an experienced and dedicated professional with a deep commitment to flawless customer service. If you need help with any SQL Server Performance Tuning Issues, please feel free to reach out at pinal@sqlauthority.com.

Pinal is also a CrossFit Level 1 Trainer (CF-L1) and CrossFit Level 2 Trainer (CF-L2).

Nupur Dave is a social media enthusiast and an independent consultant. She primarily focuses on the database domain, helping clients build short and long-term multi-channel campaigns to drive leads for their sales pipeline.

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