小编ami*_*ana的帖子

我正在写一个查询,但它总是说"找不到匹配的索引".我不知道为什么.我的代码如下:

Query query = pm.newQuery(Classified.class);
query.setFilter("emp_Id == emp");
query.setOrdering("upload_date desc");
query.declareParameters("String emp");
List<Classified> results = (List<Classified>)query.execute(session.getAttribute("emp_Id").toString()); 

<?xml version="1.0" encoding="utf-8"?>
<datastore-indexes autoGenerate="true">
  <datastore-index kind="Classified" ancestor="false">
    <property name="emp_Id" direction="asc" />
    <property name="category" direction="asc" />
    <property name="upload_date" direction="desc" />
  </datastore-index>
</datastore-indexes> 

我已经添加了上面的索引,但它没有帮助.