Hibernate4.1中createSQLQuery使用查询缓存

 1.在hibernate中createQuery执行hql查询的时候使用查询缓存:

 

  
  
  
  
  1. getSession().createQuery(hql).setCacheable(true).setCacheRegion("user").list(); 

2.在hibernate中createSQLQuery执行sql时使用查询缓存:

 

  
  
  
  
  1. getSession().createSQLQuery(sql).setResultTransformer(Transformers.aliasToBean(User.class)).setCacheable(true).setCacheRegion("user").list(); 

这样会报错,原因是That's because the aim of the second level cache is to (ultimately) cache entities that Hib knows about. I haven't verified this but I'm not surprised that caching sql query doesn't work as those are not (directly) translated by hibernate into entities. 

解决方法:

It's solutioned adding column's types to the query, using the method "addScalar()"

like this:

 

  
  
  
  
  1. getSession().createSQLQuery(sql).addScalar("id", IntegerType.INSTANCE) 
  2. .addScalar("name",StringType.INSTANCE) 
  3. .addScalar("age",IntegerType.INSTANCE).setResultTransformer(Transformers.aliasToBean(User.class)) 
  4. .setCacheable(true).setCacheRegion("user").list(); 

ps:hibernate4中addScalar不再是Hibernate.String而是StringType.INSTANCE.docs:http://docs.jboss.org/hibernate/orm/4.1/javadocs/org/hibernate/type/Type.html

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