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POlinQ group by/select - object reference not set to an instance of an object
 

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  1. POlinQ group by/select - object reference not set to an instance of an object
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    <p>I'm trying to create a linQ query which will yield the same outcome as this SQL:</p> <pre><code>SELECT Priority.PriorityKey, Count(Priority.PriorityKey) AS NewPresentingUnits FROM Priority INNER JOIN SupportPeriod ON Priority.PriorityCode = SupportPeriod.PriorityCode WHERE (((SupportPeriod.NewClient)=True) AND ((SupportPeriod.DateAssistanceRequested) Between #1/1/2013# And #2/1/2013#) AND ((SupportPeriod.DateFinished) Between #1/1/9999# And #12/31/9999#)) GROUP BY Priority.PriorityKey; </code></pre> <p>I get the following result when i run the SQL query:</p> <p><a href="https://docs.google.com/file/d/0B6b_N7sDgjmvRlBtT1lZWURERVU/edit?usp=sharing" rel="nofollow">https://docs.google.com/file/d/0B6b_N7sDgjmvRlBtT1lZWURERVU/edit?usp=sharing</a></p> <p>This is the linQ statement:</p> <pre><code> SupportPeriodTableAdapter spTa = new SupportPeriodTableAdapter(); SupportPeriodDataTable dataTables = spTa.GetData(); var test = (from sp in dataTables where (sp.NewClient == true) &amp;&amp; (sp.DateAssistanceRequested &gt;= new DateTime(2013, 1, 1) &amp;&amp; sp.DateAssistanceRequested &lt;= new DateTime(2013, 2, 1)) &amp;&amp; (sp.DateFinished &gt; new DateTime(2013, 2, 1)) group sp by sp.PriorityRow.PriorityKey into groupz select new { Key = groupz.Key, sount = groupz.Count() }); </code></pre> <p>When i try to debug <code>var test</code> i get "object reference not set to an instance of an object" in the results view.</p> <p><a href="https://docs.google.com/file/d/0B6b_N7sDgjmvdGp0bjJCNkE3TTg/edit?usp=sharing" rel="nofollow">https://docs.google.com/file/d/0B6b_N7sDgjmvdGp0bjJCNkE3TTg/edit?usp=sharing</a></p> <p>I'm new to using 'group by' and 'select new' features of linQ, thus i'm having a hard time figuring this out....</p>
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    1. This table or related slice is empty.
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    1. PTQuestion
    1. This table or related slice is empty.
    1. USzaza
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. PO
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    1. This table or related slice is empty.
    1. CO`sp.PriorityRow` may be the culprit
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      1. POlinQ group by/select - object reference not set to an instance of an object
      1. USNSGaga
    2. CO@NSGaga All the FK's in the SupportPeriod table has a valid PK in the Priority table... do you mean i should use multiple queries and not use sp.PriorityRow?
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      1. POlinQ group by/select - object reference not set to an instance of an object
      1. USzaza
 

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