可是我执行后查不出结果

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可是改成如下不用参数可以找出结果：
<?xml version="1.0" encoding="UTF-8"?>
<root xmlns:sql='urn:schemas-microsoft-com:xml-sql'>
<sql:query>
 select * from book
 where name like '%a%'
 for XML auto,elements
</sql:query>
</root>

找出的结果：
  <?xml version="1.0" encoding="UTF-8" ?>
- <root xmlns:sql="urn:schemas-microsoft-com:xml-sql">
- <book>
  <id>1</id>
  <name>Beginning ASP.NET 1.1 With Visual C#.NET 2003</name>
  <ISBN>7-302-09148-X</ISBN>
  <author>Chris Ullman John Kauffman</author>
  <publisher>WROX PRESS.LTD</publisher>
  <price>30</price>
  </book>
- <book>
  <id>2</id>
  <name>Design Patterns Elements of Reusable Object-Oriented Software</name>
  <ISBN>7-111-09507-3</ISBN>
  <author>Erich Gamma Richard Helm Ralph Johnson John Vlissides</author>
  <publisher>Pearson Education</publisher>
  <price>38</price>
  </book>
- <book>
  <id>3</id>
  <name>UML Distilled: A Brief Guide to the Standard Object Modeling Language</name>
  <ISBN>ISBN 0321193687</ISBN>
  <author>Martin Fowler</author>
  <publisher>Addison-Wesley</publisher>
  <price>34</price>
  </book>
  </root>
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为什么我用参数无法实现这种模糊查询呢？拜托大家帮我想一个办法．急！