title: Simple SQL query too long
body: <p>I just have a simple query. On SQL Server 2008, sometimes it queries too long, nearly hang, sometimes not. The same sql on Oracle server, it always return at once.</p>
  
  <pre><code>SELECT D.DESCITEM, D.LONGDESC, D.DESCTABL, D.DESCCOY, D.DESCPFX 
  FROM VM1DTA.DESCPF D, VM1DTA.ITEMPF I 
  WHERE D.DESCPFX='IT'AND D.DESCITEM=I.ITEMITEM AND I.VALIDFLAG='1' 
  AND D.DESCTABL = I.ITEMTABL AND D.DESCCOY = I.ITEMCOY AND "LANGUAGE" =  'E' 
  AND "VALIDFLAG" =  '1' AND DESCTABL IN('T1680') 
  ORDER BY LONGDESC ASC;
  </code></pre>
  
  <p>Each table has about 100k records. </p>
  
  <p>Could someone point me about the root cause? Thanks</p>