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    <p>There is multiple aspects to consider:</p> <ul> <li>You do not have an <code>index</code> on the bookName column: in this context that does not matter, the query is going to perform the same way by executing a clustered index scan or a table scan. </li> <li>You do have a <code>non clustered index</code> on the bookName column <ul> <li>this is a <code>non covering index</code> (scenario 1): in the second use case with the <code>OR</code> statement, you are likely to hit the <code>index tipping point</code>, where the query optimizer will decide <strong>not</strong> to use the <code>non clustered index</code>. In this context the <code>LIKE</code> will perform better by using an index scan. Read more on the <a href="http://www.sqlskills.com/BLOGS/KIMBERLY/category/The-Tipping-Point.aspx" rel="nofollow noreferrer">Kimberly Tripp's blog</a>. </li> <li>this is a <code>covering index</code> (scenario 2): there is no tipping point for covering indexes. In this case, the second query will perform drastically better by using an <code>index seek</code> where the <code>LIKE</code> query will still have to do an <code>Index Scan</code>.</li> </ul></li> </ul> <p>So if performance is critical, use a covering index</p> <p>Here are the details, using <a href="http://msftdbprodsamples.codeplex.com/releases/view/93587" rel="nofollow noreferrer">Adventure Works</a></p> <p>Scenario 1</p> <pre><code>SELECT * FROM Production.Product AS p WHERE Name LIKE '%mountain seat%' SELECT * FROM Production.Product AS p WHERE Name = 'LL Mountain Seat Assembly' OR Name = 'ML Mountain Seat Assembly' OR Name = 'HL Mountain Seat Assembly' OR Name = 'LL Mountain Seat/Saddle' OR Name = 'ML Mountain Seat/Saddle' OR Name = 'HL Mountain Seat/Saddle' </code></pre> <p><img src="https://i.stack.imgur.com/CPB1K.png" alt="enter image description here"></p> <p>Scenario 2</p> <pre><code>SELECT Name FROM Production.Product AS p WHERE Name LIKE '%mountain seat%' SELECT Name FROM Production.Product WHERE Name = 'LL Mountain Seat Assembly' OR Name = 'ML Mountain Seat Assembly' OR Name = 'HL Mountain Seat Assembly' OR Name = 'LL Mountain Seat/Saddle' OR Name = 'ML Mountain Seat/Saddle' OR Name = 'HL Mountain Seat/Saddle' </code></pre> <p><img src="https://i.stack.imgur.com/nj3TS.png" alt="enter image description here"></p>
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    1. POShould I use OR statements or LIKE statements in SQL Server?
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    1. POShould I use OR statements or LIKE statements in SQL Server?
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    1. COThanks, yea I spent some time modifying the query, and I got about the same execution time for both types of queries, one with only a `LIKE` statement and another one with `OR` statements. Like you predicted, since the column is not indexed, the `LIKE` statement preformed a second better.
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