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sql to hql throwing exception

I'm using hibernate in my project and I'm trying to convert an existing sql query from DaoImplementation class to hql,
The sql query I have is
JdbcTemplate select = new JdbcTemplate(dataSource);
String sql = "SELECT * FROM (SELECT site_id,rtc,sigplan,cycle_time,health,phase_no,phase_time,active_groups,groupscolour,ip "+
"FROM status_data where rtc>='" + fromDate + "' and rtc<'" + toDate + "' and "+
"site_id=" + SiteId + " order by rtc desc limit "+recordLimit+" )as temp ORDER BY RTC ASC";
I wrote the hql version to get data from HealthLog table as
String hql = " select f from (select h from HealthLog h where rtc>='"+fromDate+"' and rtc <'"+toDate+"' "
+ "and siteId = "+siteId+" order by rtc desc limit "+limit+" ) as f order by rtc asc ";
return super.readListByHql(hql);
But the above hql throws the following exception
org.hibernate.hql.internal.ast.QuerySyntaxException: unexpected token: ( near line 1, column 16 [ select f from (select h from com.traff.hibernate.model.HealthLog as h where rtc>='1974-08-01 14:10:00.0' and rtc <'1974-09-01 23:46:20.6' and siteId = 20 order by rtc desc limit 50000 ) as f order by rtc asc ]
at org.hibernate.hql.internal.ast.QuerySyntaxException.convert(QuerySyntaxException.java:54)
at org.hibernate.hql.internal.ast.QuerySyntaxException.convert(QuerySyntaxException.java:47)
at org.hibernate.hql.internal.ast.ErrorCounter.throwQueryException(ErrorCounter.java:79)
at org.hibernate.hql.internal.ast.QueryTranslatorImpl.parse(QueryTranslatorImpl.java:276)
at org.hibernate.hql.internal.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:180)
at org.hibernate.hql.intern
I also tried the below code snippet but that giving me wrong results
Criteria criteria = createEntityCriteria();
criteria.add(Restrictions.ge("rtc", fromDate));
criteria.add(Restrictions.lt("rtc", toDate));
criteria.add(Restrictions.eq("siteId", siteId));
criteria.setMaxResults(limit);
criteria.addOrder(Order.asc("rtc"));
criteria2 = criteria;
criteria2.addOrder(Order.desc("rtc"));
return criteria2.list();
Which is the correct way to achieve the result?

First of all, as already mentioned in the comments, you cannot do a subquery within the FROM clause in HQL.
See: Hibernate Documentation
Secondly, the limit keyword is not supported by HQL.
Usually you would use query.setFirstResult(0) and query.setMaxResults(recordLimit) methods where query has the type of the Query Interface. But since you are using the limit in a subquery, there is no way.
See: How to set a limit to inner query in Hibernate?
Some options:
Use a native SQLQuery
Since you are only sorting in the outer Query. You could only execute the inner query and sort in Java.
Example for Option 2:
Session session = factory.openSession();
Query query = session
.createQuery("FROM HealthLog "
+ "WHERE rtc >= :rtcL and rtc < :rtcG and siteId = :siteId "
+ "ORDER BY rtc DESC");
query.setParameter("rtcL", fromDate);
query.setParameter("rtcG", toDate);
query.setParameter("siteId", siteId);
query.setFirstResult(0);
query.setMaxResults(recordLimit);
List<HealthLog> res = query.list();
session.close();
Collections.sort(res, new Comparator<HealthLog>() {
public int compare(HealthLog o1, HealthLog o2) {
return o1.getRtc().compareTo(o2.getRtc());
}
});
The query above returns HealthLogs with all attributes. If you want to only retrieve specific attributes, you can add a SELECT new HealthLog(siteId,rtc,sigplan,cycle_time,...) to your Query with a fitting constructor in HealthLog.
Please note that the code snippet might not be ready to use, since i do not know your model and attribute names.

mysql order by field equivalent in hibernate

How do I accomplish this custom sort by field feature available in MySQL in hibernate?
select * from pet order by field(species, 'cat', 'dog', 'bird');
For some business reason, I need to enforce a custom ordering.
PS -I am new to hibernate.

I ended up writing an HQL like this
commaDelimitedSpecies = "'cat', 'dog', 'bird'";
orderBySpecies = " ORDER BY FIELD(species, " + commaDelimitedSpecies + ") DESC";
Query q = getSession().createQuery("FROM PetModel pet" + orderBySpecies);

With Spring HibernateDAO:
getHibernateTemplate().findByNamedParametersQuery(
"FROM MyEntity me WHERE me.id IN :ids ORDER BY FIELD(id, :ids)", new String[] {"ids"}, new Object[] {uuidList.toArray()},uuidList.size()
);
Note: getHibernateTemplate returns an instance of org.springframework.orm.hibernate3.HibernateTemplate

Hibernate many-to-many retrieve list with condition

Im working with hibernate and java. I have an Group class and a User class. They share a many-to-many relationship as shown in this ERD .
What Im trying to achieve is that I want to retrieve a list of groups with the condition that they contain a User with a certain User_id.
In the GroupDao I have defined a function retrieveForUser in which I tried to retrieve the list using hibernate query language:
public List<Group> retrieveForUser(int userid){
Session session = HibernateUtil.getSessionFactory().getCurrentSession();
session.beginTransaction();
String hql = "select distinct g from Group g " +
"join g.allGroupMembers u " +
"where u.id = :id";
Query query = session.createQuery(hql).setResultTransformer(Transformers.ALIAS_TO_ENTITY_MAP);
query.setParameter("id", userid);
List<Group> list = query.list();
session.getTransaction().commit();
return list;
}
When I try to loop throught the resulting list using:
for(Group g : groupDao.retrieveForUser(user1.getId())){
System.out.println(g.getName());
}
I get the following errormessage:
java.lang.ClassCastException: java.util.HashMap cannot be cast to nl.hu.jelo.domain.group.Group
Question
How can I achieve it so that I end up with an List<Group> with only groups that contain a User with an certain User_id

You do not need to set result transformer. ALIAS_TO_ENTITY_MAP is for other purpose.
Simply do
String hql = "select distinct g from Group g " +
"join g.allGroupMembers u " +
"where u.id = :id";
Query query = session.createQuery(hql);
query.setParameter("id", userid);
is good enough.
Something off topic, are you sure you want to handle transaction manually like that?

Setting ORDER BY and LIMIT clause on JPA Query

I'm very, very new to Hibernate and JPA. I want to be able to apply ORDER BY and LIMIT clauses to a Hibernate(?) query, but am coming up empty. NOTE: I inherited this code.
Here is the current code:
public SomeCoolResponse getSomeCoolResponse(String myId) {
String queryString = "select aThing from AWholeBunchOfThings aThing " +
"join aThing.thisOtherThing oThing join oThing.StillAnotherThing saThing " +
"where saThing.subthing.id = :id";
Query q = getEntityManager().createQuery(queryString);
q.setParameter("id", myId);
List<MyThings> list = q.getResultList();
if(list.size() > 0) {
return list.get(0);
}
return null;
}
Instead of getting an entire list and then just returning the first result (which is the only one we need), I'd like to be able to apply a LIMIT 0,1 clause so that the query will be faster. Also, the query needs to be sorted descending on aThing.created which is a UNIX timestamp integer.
I've tried altering queryString like this:
String queryString = "select aThing from AWholeBunchOfThings aThing " +
"join aThing.thisOtherThing oThing join oThing.StillAnotherThing saThing " +
"where saThing.subthing.id = :id ORDER BY aThing.created LIMIT 0,1";
But Hibernate still returns the entire set.
I've looked at using the JPA CriteriaBuilder API, but it hurt my brain.
I'm a total n00b when it comes to this, and any help is greatly appreciated!

I think you need
q.setMaxResults(1);
See also the accepted answer here.
How do you do a limit query in HQL?
As to the "order by" clause you may include it in the queryString.

The JPQL equivalent to LIMIT start,max is:
setFirstResult and setMaxResults:
q.setFirstResult(start);
q.setMaxResults(limit);

How to Count the rows in Hibernate Query Language?

I am trying to get just the count of the rows returned rather than all the results from the table.
I saw that this can be done like this:
( (Integer) session.createQuery("select count(*) from ....").iterate().next() ).intValue()
But when trying to store this query in an integer format(it says cannot convert from Query to Integer)
I am using a dynamic query where the values will be mentioned below the query like this
theQuery = "select count(*) from THM as thm " +
"join thm.TMC as tmc " +
"join tmc.TIMCC as timcc " +
"where thm.Qid = :Qid and thm.Cv = :Cv and timcc.Did = :Did and timcc.Cv= :Cv";
Query query = session.createQuery(theQuery);
query.setInteger("Qid", Integer.parseInt(Qid));
query.setInteger("Did", Did);
query.setInteger("Cv",cV);
Now, how can i get a count of all the rows returned by using Hibernate query in a variable without using list.size but directly from the query?

Have you tried the query.uniqueResult(); ? As your Select count(*) will give you only one number, you should be able to retrieve it with this like int count = (Integer)query.uniqueResult();
To count based on a Criteria you can do this:
Criteria criteria = currentSession().createCriteria(type);
criteria.setProjection(Projections.rowCount());
criteria.uniqueResult();
I'm using the Criteria right now so I know for sure that it works. I saw the uniqueResult() solution on a website here: http://www.jroller.com/RickHigh/entry/hibernate_pagination_jsf_datagrid_prototype1

you can do this
long count = (long)session.createQuery("SELECT COUNT(e) FROM Employees e").getSingleResult();

Try it.
Long count = ((Long) session.createQuery("select count(*) from Book").uniqueResult());
Integer totalBooks = count.intValue();

Work for me
int list=(int)
sessionFactory.getCurrentSession().createSQLQuery("select count(*) as count from
Book").addScalar("count",IntegerType.INSTANCE).uniqueResult();