I’m an outspoken advocate of always using a clustered index on each and every table you create as a matter of best practice. But even I will agree that there’s a case for using the odd heap now and then.
heap
Indexing basics
Understanding indexes in SQL Server can help you build much more efficient database solutions. Often, performance problems can be adressed with indexes, so knowing how indexes work and how to set them up for the best performance are a great asset in your optimization work.
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