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POJava coding best-practices for reusing part of a query to count
 

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    <p>The <a href="https://stackoverflow.com/questions/1600215/implementing-result-paging-in-hibernate-getting-total-number-of-rows">implementing-result-paging-in-hibernate-getting-total-number-of-rows</a> question trigger another question for me, about <strong>some implementation concern</strong>:</p> <p>Now you know you have to reuse part of the HQL query to do the count, how to reuse efficiently?</p> <p>The differences between the two HQL queries are:</p> <ol> <li>the selection is <code>count(?)</code>, instead of the pojo or property (or list of)</li> <li>the fetches should not happen, so some tables should not be joined</li> <li>the <code>order by</code> should disappear</li> </ol> <p>Is there other differences?</p> <p>Do you have <strong>coding best-practices to achieve this reuse efficiently</strong> (concerns: effort, clarity, performance)?</p> <p>Example for a simple HQL query:</p> <pre><code> select a from A a join fetch a.b b where a.id=66 order by a.name select count(a.id) from A a where a.id=66 </code></pre> <hr> <p><strong>UPDATED</strong></p> <p>I received answers on:</p> <ul> <li>using <em>Criteria</em> (but we use HQL mostly)</li> <li><em>manipulating the String</em> query (but everybody agrees it seems complicated and not very safe)</li> <li><em>wrapping the query</em>, relying on database optimization (but there is a feeling that this is not safe)</li> </ul> <p>I was hoping someone would give options along another path, more related to String concatenation.<br> <strong>Could we build both HQL queries using common parts</strong>?</p>
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