如何制作HQL查询对象而不是db？

Question

I am new to HQL and this thing confuses the heck out of me. So, this is the function I have:

public List<Map<String, Object>> getMyQuery(List<Country> country){
    String hql = "SELECT DISTINCT new map(a as accounts) ";
    hql += "FROM Account a WHERE a.location_id in "
                + "( "
                + "SELECT location_id FROM Location l WHERE l.address_id in "
                + "("
                + "SELECT id FROM Address adr WHERE adr.country_id in (:country)))";

    }
    Query query = getSession().createQuery(hql);
    if(country != null){
        query.setParameterList("country", country);
    }
    return query.list();
}

In my log files, I saw that the query could not be resolved due to:

 Caused by: org.hibernate.QueryException: could not resolve property: country_id of: com.mypackage.myobjects.Address [SELECT id FROM com.mypackage.myobjects.Address adr WHERE adr.country_id in (:country)]

When I run the similar query on the using SQL db, everything is fine, but this one breaks. I was wondering why is that all of a sudden outputs package in the folders? It seems that the query is being executed on the objects, not the database. What am I doing wrong?

Thank you in advance

Answer 1

As error log says, hibernate is unable to find property named "country_id" in class "com.mypackage.myobjects.Address". May be country_id is name of column from address table.

Hql works on Pojo's, try mapping property from Address class that is mapped with counrty_id column. Please refer to

If Address class is,
Class Address{

 @Column(name="country_id")
 private int countryId;

  ....
}

then replace "country_id" in hql query with "countryId"