Do all of your tables contain clustered indexes? Some say every table should have a clustered index. Others say it depends. When databases are being designed and developed, your developers might have overlooked creating clustered indexes on some of your database tables. Having a useful clustered index on your tables will improve the performance of your queries, especially if you are returning data periodically in order by the clustered index key. Here is a simple script to identify those tables in your database that don’t have a clustered index.
-- Tables without clustered indexes
SELECT TOP 1000 o.name, i.type_desc, o.type_desc, o.create_date
FROM sys.indexes i
INNER JOIN sys.objects o
ON i.object_id = o.object_id
WHERE o.type_desc = 'USER_TABLE'
AND i.type_desc = 'HEAP'
ORDER BY o.name;
GO
See all articles by Greg Larsen
Gregory A. Larsen is a DBA at Washington State Department of Health (DOH). Greg is responsible for maintaining SQL Server and other database management software. Greg works with customers and developers to design and implement database changes, and solve database/application related problems. Greg builds homegrown solutions to simplify and streamline common database management tasks, such as capacity management.
DatabaseJournal.com publishes relevant, up-to-date and pragmatic articles on the use of database hardware and management tools and serves as a forum for professional knowledge about proprietary, open source and cloud-based databases--foundational technology for all IT systems. We publish insightful articles about new products, best practices and trends; readers help each other out on various database questions and problems. Database management systems (DBMS) and database security processes are also key areas of focus at DatabaseJournal.com.
Property of TechnologyAdvice. © 2026 TechnologyAdvice. All Rights Reserved
Advertiser Disclosure: Some of the products that appear on this site are from companies from which TechnologyAdvice receives compensation. This compensation may impact how and where products appear on this site including, for example, the order in which they appear. TechnologyAdvice does not include all companies or all types of products available in the marketplace.