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hql in-clause with multiple hits in child collection

I have a table/entity called Recipe with a child collection of type Tag.
I want to be able to find a Recipe searching by two or more tags. Something like:
SELECT re FROM Recipe re JOIN re.tags t WHERE t in :tagsIds
but I only want those hits where the Tag collection contains all tagIds.
Is it possible in HQL/SQL? (Maybe using Criteria?)
Thanks in advance.

I am assuming you have two different entities Recipe and Tag, it can be done as below.
Criteria criteria = getSession().createCriteria("Recipe.class");
criteria.createAlias("tags", "tag");
criteria.add(Restrictions.in("tag.id", Arrays.asList(1,2,3)));
return (List<Recipe>) criteria.list();

I believe you may be missing parentheses in the HQL. It should be:
... WHERE t in (:tagsIds)

Ok, so this did it. Thanks for the replies.
String hql = "select r from Recipe r " +
"join r.tags t " +
"where t.id in (:tags) " +
"group by r " +
"having count(t)=:tag_count";
Query query = session.createQuery(hql);
query.setParameterList("tags", tagIds);
query.setInteger("tag_count", tagIds.size());
List<Recipe> recipes = query.list();

Group by in HQL and Hibernate Criteria queries (ORA-00979: not a GROUP BY expression)

I am new to new to hibernate and Java, so I apologize if these are ridiculously simply questions.
I don't understand why the following query gives me the error "ORA-00979: not a GROUP BY expression".
Query q = session.createQuery (
"select new tdata.Summary(tbForm.rYear, SUM(tbForm.pWaste)) "
+ "from TrForm tbForm "
+ "left join fetch tbForm.indKey "
+ "where tbForm.indKey.grpCode='999' "
+ "group by tbForm.rYear " );
The possible reasons for this error do not seem to apply to my query because I am including group by function SUM, and I do not have any expressions in the select that are not in the group by.
I also tried to write a criteria query to do what I need, and I could not get that to work either. In the criteria version, I am confused as to how to add restrictions to fetched data and how to get the data into the Summary object.
Criteria criteria = session.createCriteria(TrForm.class)
.setFetchMode("DimInd",FetchMode.JOIN)
.add(Restrictions.eq("indKey.indCode", "999"))
.setProjection(Projections.projectionList()
.add(Projections.groupProperty("rYear"))
.add(Projections.sum("pWaste")));
summaryList = (List<Summary>) criteria.list();
Any help would be greatly appreciated.
Thanks!
Update:
Thank you so much! I removed the "left join fetch tbForm.indKey" and the HQL version worked!
Generalized query is
select R_YEAR, sum(P_WASTE)
from TR_FORM tbForm
left join DIM_IND ind
on tbForm.IND_KEY = ind.IND_KEY
where ind.GRP_CODE='999'
group by tbForm.R_YEAR
tdata is the folder in which I have the java code for the data models.

HQL right join empty list

I am using hql with hibernate. I've tried to write a query over three tables. The tables are Medientyp, RaumMedientyp and Raum. I wanna read all Medientyp's from the whole table and all RaumMedientyp's from a specific raumId.
The realtions between the tables are:
Medientyp 1 <--> mc RaumMedientyp mc <--> 1 Raum
I need all as RaumMedientyp Entity.
The query i tried is:
String hql = "from RaumMedientyp rm right join rm.medientyp m inner join rm.raum r where r.id = :raumId";
Query query = getSession().createQuery(hql);
query.setInteger(":raumId", raumId);
But if i'm executing
query.list();
i've got a empty list as return.

How to join two unrelated entities using JPA and Hibernate

I have two tables - one containing Address and another containing Photographs. The only common field between them is the PersonID. These were mapped to two POJO Classes Address and Photo. I was able to fetch details in these tables by creating criteria and adding restrictions on the fields . How should we write a join on the two tables. Is it possible to get the result as two objects -Address and Photo.
I want to do a left join so that i can get records of persons without photos as well.
I have read that this is possible only using hql but Can this be done using criterias as well?

You can easily write HQL query that will return result as two objects using Theta Join (as Adrian noted). Here is an example:
String queryText = "select address, photo from Address address, Photo photo "
+ " where address.personID=photo.personId";
List<Object[]> rows = session.createQuery(queryText).list();
for (Object[] row: rows) {
System.out.println(" ------- ");
System.out.println("Address object: " + row[0]);
System.out.println("Photo object: " + row[1]);
}
As you can see query returns list of Object[] arrays that represents each fetched row. First element of this array will contain one obejct and second element - another.
EDIT:
In case of left join I think you need to use native SQL query (not HQL query). Here how you can do this:
String queryText = "select address.*, photo.* from ADDRESS address
left join PHOTO photo on (address.person_id=photo.person_id)";
List<Object[]> rows = sess.createSQLQuery(queryText)
.addEntity("address", Address.class)
.addEntity("photo", Photo.class)
.list();
This should work for your case.

Basically, you have two options:
Since Hibernate 5.1, you can use ad-hoc joins for unrelated entities.
Tuple postViewCount = entityManager.createQuery(
"select p as post, count(pv) as page_views " +
"from Post p " +
"left join PageView pv on p.slug = pv.slug " +
"where p.title = :title " +
"group by p", Tuple.class)
.setParameter("title", "High-Performance Java Persistence")
.getSingleResult();
Prior to Hibernate 5.1, you could only use theta-style joins. However, a theta-style join is equivalent to an equijoin, hence you can only emulate INNER JOINs not OUTER JOINs.
List<Tuple> postViewCount = entityManager.createQuery(
"select p as post, count(pv) as page_views " +
"from Post p, PageView pv " +
"where p.title = :title and " +
" ( p.slug = pv.slug ) " +
"group by p", Tuple.class)
.setParameter("title", "Presentations")
.getResultList();

Finally after 12 years the Hibernate team has implemented such a feature
From Hibernate docs:
The FROM clause can also contain explicit relationship joins using the join keyword. These joins can be either inner or left outer style joins.
List<Person> persons = entityManager.createQuery(
"select distinct pr " +
"from Person pr " +
"join pr.phones ph " +
"where ph.type = :phoneType", Person.class )
.setParameter( "phoneType", PhoneType.MOBILE )
.getResultList();
List<Person> persons = entityManager.createQuery(
"select distinct pr " +
"from Person pr " +
"left join pr.phones ph " +
"where ph is null " +
" or ph.type = :phoneType", Person.class )
.setParameter( "phoneType", PhoneType.LAND_LINE )
.getResultList();
Or you can use WITH and ON keywords. A remark on those
The important distinction is that in the generated SQL the conditions
of the WITH/ON clause are made part of the ON clause in the generated
SQL, as opposed to the other queries in this section where the
HQL/JPQL conditions are made part of the WHERE clause in the generated
SQL.
Example
List<Object[]> personsAndPhones = session.createQuery(
"select pr.name, ph.number " +
"from Person pr " +
"left join pr.phones ph with ph.type = :phoneType " )
.setParameter( "phoneType", PhoneType.LAND_LINE )
.list();
I am currently eager to try the new feature.

Joining two unrelated entities are possible in Hibernate 5.1.
Eg :
select objA from ObjectA objA
JOIN ObjectB objB on objB.variable = objA.variable
where objA.id = 1

It's best to have a class containing those classes you want to join to have them all together.
But if you are joining these tables just for some occasional purposes, you can use criteria and manually load data from each table and put them together. (and yes, you can have these tables' data separately if for Address and Photo there are two separate classes and tables)

What you are looking for is
HQL
Join on fields that you haven't modeled as relationships
Left Join
(During the time the question was first asked and this answer was given) Hibernate supports Theta Join which allows you to do 1 & 2. However, only inner join is available for theta join style.
Personally I would recommend you to model proper relationships, so you just need 1 & 3 which is well-supported in HQL.
(Another answer actually provided an update on new Hibernate feature that provides such feature, that you may simply refer to)

Can I convert this Mysql query to JPA?

I'm fairly familiar with SQL but very new to the Java Persistence API. I'm using JPA through the Play Framework.
I have the following MySql query that I'd like to convert to pure JPA code if I can:
SELECT a.id, b.id
FROM Rankable a
INNER JOIN Rankable b on a.id < b.id
WHERE
a.category_id = ? AND b.category_id = ?
AND NOT EXISTS (
SELECT *
FROM Comparison c
WHERE c.lower in (a.id, b.id))
AND NOT EXISTS (
SELECT *
FROM Comparison c
WHERE c.higher IN (a.id, b.id))
ORDER BY a.id * rand()
LIMIT 1;
The purpose of this query is to select two rows from the Rankable table, but ensure that this specific pair is not present in the Comparison table.
What would be the best way to call a somewhat complicated query like this from Play/JPA?

It is possible to do a self join in JPA.
Take a look at this example
from the example
#NamedQuery(name="siblings", query="select distinct sibling1 "
+ "from Deity sibling1, Deity sibling2 where "
+ "sibling1.father = sibling2.father "
+ "and sibling1.mother = sibling2.mother "
+ "and sibling2 = ?1 and sibling1 <> ?1"),