title: SQL Error: Invalid object name 'Table name'
body: <p>I have 2 tables as below:</p>
  
  <pre><code>tblTransaction
  tblMobileRegistration
  </code></pre>
  
  <p>I want to join these 2 tables and count the numbers of raws that specific columns value in that is not '1' as below:</p>
  
  <pre><code>SELECT COUNT(Transaction_MobileErrorCode) FROM T1 WHERE Transaction_MobileErrorCode &lt;&gt; ''
  </code></pre>
  
  <p>Its my whole query:</p>
  
  <pre><code>SELECT 
  T1.*, 
  T2.*,  
  (SELECT COUNT(Transaction_MobileErrorCode) FROM T1 WHERE Transaction_MobileErrorCode &lt;&gt; '')  
  FROM 
  (SELECT MobileRegistration_DateTime, Transaction_MobileErrorCode FROM tblTransaction, tblMobileRegistration
   WHERE T1.ID1 = T2.ID1 AND 
        T1.ID2 = '111111' AND
        T1.ID3 = '222222' AND
        T1.ID4 = '333333' AND
        T1.ID5 = '444444') AS T1,
  
        tblMobileRegistration AS T2
  </code></pre>
  
  <p>but I got this error:</p>
  
  <pre><code>Invalid object name 'T1'.
  </code></pre>
  
  <p>so how can I fix it?
  thanks for any helping...</p>