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Creating dynamic query using jpa criteria

I created dynamic query using jpa criteria but an extra pair of parentheses gets added to columns to be selected when I do userGroupSubquery.select(userGroupsRoot);
generated query
select (securitygr3_.group_name, securitygr3_.user_name) from gm.security_groupings securitygr3_ where 1=1 and securitygr3_.user_name='xxx' and (securitygr3_.group_name in ('XYZ'))
expected query:
select securitygr3_.group_name, securitygr3_.user_name from gm.security_groupings securitygr3_ where 1=1 and securitygr3_.user_name='xxx' and (securitygr3_.group_name in ('XYZ'))
Subquery<SecurityGroupings> userGroupSubquery = secUsersQuery.subquery(SecurityGroupings.class);
Root<SecurityGroupings> userGroupsRoot = userGroupSubquery.from(SecurityGroupings.class);
Path<SecurityGroupingsId> secGroupId = userGroupsRoot.get("id");
Path<SecurityUsers> secUsers = secGroupId.get("securityUsers_1");
Path<SecurityUsers> securityUsers = secGroupId.get("securityUsers");
Path<String> su_name = secUsers.get("name");
Path<String> name = securityUsers.get("name");
userGroupSubquery.select(userGroupsRoot);
userGroupSubquery.getCompoundSelectionItems();
//userGroupSubquery.where(criteriaBuilder.equal(pet.get(SecurityGroupingsId_.id), root.<String>get("name")));
Predicate restrictions3 = criteriaBuilder.conjunction();
restrictions3 = criteriaBuilder.and(restrictions3, criteriaBuilder.and(criteriaBuilder.equal(su_name, dto.getUserId().trim().toUpperCase())));
restrictions3 = criteriaBuilder.and(restrictions3, criteriaBuilder.and(name.in(userGroups)));
userGroupSubquery.where(restrictions3);
restrictions = criteriaBuilder.and(restrictions, criteriaBuilder.exists(userGroupSubquery));
}
secUsersQuery.where(restrictions);
Its just that I get an extra pair of parentheses at select (securitygr3_.group_name, securitygr3_.user_name) from
which gives me ora-00907 missing right parenthesis error. I am sure it is coming from userGroupSubquery.select(userGroupsRoot) but I am not sure why. Please help

I got the solution for the above. When the entity has a composite key, then in JPA criteria instead of doing
userGroupSubquery.select(userGroupsRoot);
we should do
userGroupSubquery.select(userGroupsRoot.get("id"));
where id is the composite id.

How to create mapping of composed object with Hibernate when using a complex sqlquery?

I am trying to use the below query with Hibernate's session.createSQLQuery.
The Entity object corresponding to user has an attribute called address.
The address object is created out of 5 fields from table 'user'.
If I do not use an SQLQuery it gets filled auto-magically.
However without the SQLQuery I can't get all the info I would get from the desired joins shown below.
The user entity object also attributes like accessPlan which I am filling up using
.addEntity("accessPlan", AccessPlan.class)
Query:
SELECT
user.*,
ap.*,
country.*,
auth.*,
GROUP_CONCAT(coup.code SEPARATOR ' ') coupons
FROM
user
INNER JOIN access_plan ap ON (user.access_plan = ap.id)
INNER JOIN country ON (user.country=country.code)
LEFT JOIN user_auth auth ON (user.id = auth.userid)
LEFT JOIN (
SELECT
trans.user_id,coupon.code
FROM
payments_transaction AS trans
INNER JOIN payments_coupon coupon ON (trans.payments_coupon_id=coupon.id)
) coup ON (user.id=coup.user_id)
GROUP BY user.id;
What can be the easiest way to fill up the composed address object while using the SQLQuery?
OR
Is there a way to avoid using SQLQuery for a query like this?

Please check below example from the section 'Returning multiple entities'
String sql = "SELECT ID as {c.id}, NAME as {c.name}, " +
"BIRTHDATE as {c.birthDate}, MOTHER_ID as {c.mother}, {mother.*} " +
"FROM CAT_LOG c, CAT_LOG m WHERE {c.mother} = c.ID";
List loggedCats = sess.createSQLQuery(sql)
.addEntity("cat", Cat.class)
.addEntity("mother", Cat.class).list()
In your case, cat = user, mother = address... somewhat like that.
I do not have anything to try out at the moment but I guess this will help.

How to query a database using Hibernate?

I understand some might simply answer this question with "Why didn't you just Google it"... But I did, and the more I researched this the more confused I got. I'm trying to query my database with Hibernate, the query has a 'where' clause.
Now creating a database entry is easy enough, in the case where I have a 'User' class, I simply do this:
// Gets a new session
Session session = HibernateUtil.getSessionFactory().openSession();
session.beginTransaction();
// Creates a new User object
User user = new User("John", "p#55w0rd*", "john#doe.com");
// Save and commit
session.save(user);
session.getTransaction().commit();
But what do I do when I what to for instance
select * from Users where id = '3';
My Google searches pointed to something called HQL, which makes me wonder why I couldn't of just used straight JDBC then. Also it doesn't seem very object oriented. And then there's something like
session.createCriteria(.......
But I'm not sure how to use this.. Any help? Thanks guys.

When you use Native Query (non HQL ) you need to tell hibernate explicitely to handle it like below :
In below query createSQLQuery is special function to handle native sql's
String sql = "SELECT * FROM EMPLOYEE WHERE id = :employee_id";
SQLQuery query = session.createSQLQuery(sql);
query.addEntity(User.class);
query.setParameter("employee_id", 3);
List<User> results = query.list();
This can be done using criteria as well for that following is good starting point:
Criteria criteria = sess.createCriteria( User.class);
List<User> users= criteria.list();
http://www.developerhelpway.com/framework/hibernate/criteria/index.php

First of all, you need a hibernate.cfg.xml which contains properties for hibernate. This is e.g url, username and password, the driver and dialect. This file is placed in a package called resources.
You have to choose between using Hibernate Annotations example
or using hbm.xml files example
This is how you tell hibernate what your database is like. It wil automatically create queries for you based on how you annotates or defines in e.g user.hbm.xml.
Create a HibernateUtil.java class which holds the session factory.
You can fetch data from the database with
Criteria crit = getSessionFactory().getCurrentSession().createCriteria(User.class);
Example using queries:
List<?> hibTuppleResultList = currentSession.createQuery(
"from Person p, Employment e "
+ "where e.orgno like ? and p.ssn = e.ssn and p"
+ ".bankno = ?")
.setString(0, orgNo).setString(1, bankNo).list();
for (Object aHibTuppleResultList : hibTuppleResultList)
{
Object[] tuple = (Object[]) aHibTuppleResultList;
Person person = (Person) tuple[0];
hibList.add(person);
}

In the end all I really wanted was to know that if you don't want to use HQL you get something called 'Criteria Queries', and that in my case I'd do something like this:
Criteria cr = session.createCriteria(User);
cr.add(Restrictions.eq("id", 3));
List results = cr.list();
Me: "Thanks!"
Me: "No problem :)"
PS - we can really delete this question.

Query q = session.createQuery("from User as u where u.id = :u.id");
q.setString("id", "3");
List result = q.list();
Query with Criteria:
Criteria cr = session.createCriteria(User.class);
List results = cr.list();
Restrictions with Criteria:
Criteria cr = session.createCriteria(User.class);
cr.add(Restrictions.eq("id", 3));
// You can add as many as Restrictions as per your requirement
List results = cr.list();
You could also use it like this
List results = session.createCriteria(User.class).add(Restrictions.eq("id", 3)).list();
Some example for Crieteria Rsetriction query
Criteria cr = session.createCriteria(Employee.class);
// To get records having salary more than 2000
cr.add(Restrictions.gt("salary", 2000));
// To get records having salary less than 2000
cr.add(Restrictions.lt("salary", 2000));
// To get records having fistName starting with zara cr.add(Restrictions.like("firstName", "zara%"));
// Case sensitive form of the above restriction.
cr.add(Restrictions.ilike("firstName", "zara%"));
// To get records having salary in between 1000 and 2000
cr.add(Restrictions.between("salary", 1000, 2000));
// To check if the given property is null
cr.add(Restrictions.isNull("salary"));
// To check if the given property is not null
cr.add(Restrictions.isNotNull("salary"));
// To check if the given property is empty
cr.add(Restrictions.isEmpty("salary"));
// To check if the given property is not empty
cr.add(Restrictions.isNotEmpty("salary"));
You can create AND or OR conditions using LogicalExpression restrictions as follows:
Criteria cr = session.createCriteria(Employee.class);
Criterion salary = Restrictions.gt("salary", 2000);
Criterion name = Restrictions.ilike("firstNname","zara%");
// To get records matching with OR condistions
LogicalExpression orExp = Restrictions.or(salary, name);
cr.add( orExp );
// To get records matching with AND condistions
LogicalExpression andExp = Restrictions.and(salary, name);
cr.add( andExp );
List results = cr.list();
I think this will help you

Hibernate syntax error : Expected DOT

I am getting the following error on the execution of the below hibernate transaction : expecting DOT, found '=' near line 1, column 32 [update t_credential set status = :status , assigned_engine = :engine where id = :id] .
Also, t_credential is a table and not an object. Does hibernate allow to use this way or does it compulsorily have to be an object?
for(Credential credential: accountList){
Query query = ssn.createQuery("update t_credential set status =:status , assigned_engine = :engine where id = :id");
query.setParameter("status", status);
query.setParameter("engine", assignedTo);
query.setParameter("id", String.valueOf(credential.getId()));
int result = query.executeUpate();
}

Look at the HQL example here: http://docs.jboss.org/hibernate/orm/3.3/reference/en/html/batch.html#batch-direct. It seems that you need to refer to an object: "update t_credential c", and then update it's fields, like this: "set c.status = :status" and so on.

If you want to use Hibernate with SQL Query (and not HQL query), you may have to use a different function.
ssn.createSQLQuery(" ... ");
I never used this function, so I hope it's a good answer for you.
Max

querying a table using JPA and populating a bean corresopind to a table

I have a project already developed using java,jsp and JPA (open jpa).Now i want to add a new API to retrieve data from DB.Am not much familiar with JPA.Now i want to take a join of 3 tables Atbl , Btbl, and Ctble ,then check for some conditions and finally populate bean corresopnding to table Atble.I saw a a API as follows
String sql = "SELECT A.* FROM Atble A, Btbl B WHERE A.xyz = B.pqr
AND A.field1 = ? AND B.field2 = 'SubComponent' AND B.field3 = ? ";
Query q = em.createNativeQuery(sql, A.class);
q.setParameter(1,"aa");
q.setParameter(2, "aa");
q.setParameter(3, "cc");
List<A> a = (List<A>) q
.getResultList();
Does it populate bean for A directly?If not how can i populate bean for A

This will return a List, so should work fine.
You may also consider using JPQL instead of a native SQL query, but if you are more comfortable with SQL that is fine.