title: How to defer query execution in NHibernate QueryOver
body: <p>I am trying to execute 3 queries but want to execuate all at one database call. I gone through <a href="https://ayende.com/blog/3979/nhibernate-futures" rel="nofollow">https://ayende.com/blog/3979/nhibernate-futures</a> but it still executes each query individually. I am using QueryOver instead of CreateCriteria.</p>
  
  <p>Can anyone help how to achieve this?</p>
  
  <p>my query is like</p>
  
  <pre><code>            var changedScriptsInHeader = _session.QueryOver&lt;ProgramHeader&gt;()
                                      .Where(x =&gt; x.ModifiedTime.IsBetween(changedFrom).And(changedTo))
                                      .Select(x =&gt; x.ScriptNumber)
                                      .Future&lt;string&gt;();
  
              var changedScriptsInDetail = _session.QueryOver&lt;ProgramDetail&gt;()
                                      .Where(x =&gt; x.UpdatedDate.IsBetween(changedFrom).And(changedTo))
                                      .SelectList(list =&gt; list.SelectGroup(pr =&gt; pr.ScriptNumber))
                                      .Future&lt;string&gt;();
  
              var changedScriptsInReplay = _session.QueryOver&lt;ProgramReplay&gt;()
                                      .Where(x =&gt; x.UpdatedDate.IsBetween(changedFrom).And(changedTo))
                                      .SelectList(list =&gt; list.SelectGroup(pr =&gt; pr.ScriptNumber))
                                      .Future&lt;string&gt;();
  </code></pre>
  
  <p>Thanks</p>