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How do I write join in Ebean Java ORM language

Currently my code is
int customerId = 4;
String sql = "select id from coupon as A join coupon_use "
+ "as B on A.id=B.coupon where B.customer=" + customerId
+ " and B.like_at is not null;";
RawSql rawSql = RawSqlBuilder.parse(sql).create();
Query<Coupon> query = Ebean.find(Coupon.class);
query.setRawSql(rawSql);
List<Coupon> list = query.findList();
return ok(Json.toJson(list));
How do I avoid writing manual sql query but still have the ORM generate that query and return me the result?

Ebean will add appropriate joins based on the paths/properties used in the where and order by etc.
where couponUse.likeAt is not null.
Assuming couponUse.likeAt is the correct expression path ... Ebean will add a join to support the expression automatically.

How can I get the alias name for my ResultSet from a Subquery?

I have a problem with getting the alias of the columnnames for my ResultSet.
I made a subquery, where i use the alias function(MAX(...) in SQL) but everytime I execute the Statement, I get java.sql.SQLException because the column name is not valid. And I use the current alias where I call the getString - Function of my ResultSet.
This is my SQL-Statement in Eclipse:
String sql = "SELECT a.steelgrade, a.prod_order_id, a.prod_order_item_pos, "
+"a.prod_order_version, a.strip_thickn_aim, a.strip_width_aim, "
+"a.customer, a.order_weight_plan, b.grund_kommlos, b.coil_weight "
+"FROM (SELECT prod_order_id, prod_order_item_pos, "
+ "MAX (prod_order_version) AS max_version "
+ "FROM production_order "
And in the ResultSet while.next()-Loop:
prod_order_version = AuftraegeProduction.getString("max_version");
This is the whole SQL-Statement( in the Database it works fine!):
SELECT a.steelgrade, a.prod_order_id, a.prod_order_item_pos,
a.prod_order_version, a.strip_thickn_aim, a.strip_width_aim,
a.customer, a.order_weight_plan, b.grund_kommlos, b.coil_weight
FROM (SELECT prod_order_id, prod_order_item_pos,
MAX (prod_order_version) AS max_version
FROM production_order
GROUP BY prod_order_id, prod_order_item_pos) c
JOIN
production_order a
ON a.prod_order_id = c.prod_order_id
AND a.prod_order_item_pos = c.prod_order_item_pos
AND a.prod_order_version = c.max_version
JOIN pps_plan_slab b
ON b.prod_order_id = c.prod_order_id
AND b.prod_order_item_pos = c.prod_order_item_pos
AND b.prod_order_version = c.max_version
WHERE a.strip_thickn_aim > 1.78
AND a.strip_thickn_aim < 3.26
AND a.steelgrade = 'M4R51'
AND a.prod_order_id NOT BETWEEN '0999551' AND '0999599'
AND a.strip_width_aim BETWEEN 1126 AND 1166
AND NVL (a.order_weight_plan, 0) > 0
AND a.order_weight_plan >= b.coil_weight
ORDER BY prod_order_id ASC
Anyone have a suggestion?
Maurice

when using aggregate functions max(),min(),sum(),... you must use group by clause clause.

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();

More elegant way to write a hibernate query

Can someone help me write a better code. I tried this but its not working :
Query query = session.createQuery("from MyTable order by :sortvariable :sortorder");
query.setParameter("sortvariable", sortvar);
query.setParameter("sortorder", order);
This is not working as well
Query query = session.createQuery("from MyTable table order by table." + sortvar + " " + " :sortorder");
query.setParameter("sortorder", order);
I managet to get it working with this :
Query query = session.createQuery("from MyTable table order by table." + sortvar + " " + order);
I need to do this with query because I'm using setMaxResults() and setFirstResult().

I don't think you can use parameters to identify keywords that way. Is it possible to do what you're trying to do using the criteria API?
boolean sortAscending = ...;
Criteria criteria = session.createCriteria(MyTable.class);
criteria.addOrder(sortAscending? Order.asc(sortVar): Order.desc(sortVar));