Reducing Reads In Queries

Bert Wagner has a few tips for improving query performance by reducing the number of reads:

If SQL Server thinks it only is going to read 1 row of data, but instead needs to read way more rows of data, it might choose a poor execution plan which results in more reads.

You might get a suboptimal execution plan like above for a variety of reasons, but here are the most common ones I see:

If you had a query that previously ran fine but doesn’t anymore, you might be able to utilize Query Store to help identify why SQL Server started generating suboptimal plans.

Click through for a few more ideas as well.

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