Hibernate Criteria for sum(distinct clicks) - java

I am unable to come up with the criteria which can perform sum(distinct clicks) in query. I am getting result with simple sql query but cannot make criteria to do the same.
Currently i can just do
.add(Projections.property("clicks").as("clicks"))
A simple sql query is like this
select sum(distinct clicks) as clicks, source as source, sum(jobs_sent) as jobsSent from tbl_click_count where date= '2016-09-04' and domain = 'somename' and whitelabel = 'somename' group by source, whitelabel, domain order by id desc
and my criteria is like
Criteria criteria = getSessionFactory().createCriteria(FeedClickCountModel.class)
.add(Restrictions.ge("date", startDate))
.add(Restrictions.le("date", uptoDate))
.setProjection(Projections.projectionList()
.add(Projections.sum("jobsSent").as("jobsSent"))
.add(Projections.groupProperty("source").as("source"))
.add(Projections.property("whiteLabel").as("whiteLabel"))
.add(Projections.property("domain").as("domain"))
.add(Projections.property("totalJobs").as("totalJobs"))
.add(Projections.property("clicks").as("clicks"))
// ^This i want is sum(distinct clicks)
.add(Projections.property("date").as("date"))
.add(Projections.property("id").as("id")))
.setResultTransformer(Transformers.aliasToBean(FeedClickCountModel.class));
Is there any way to do this without sqlprojection.

.add(Projections.distinct(Projections.property("clicks")));
Like this?

Projections.sum(Projections.countDistinct(propertyName));
Try this.
Without projections, you will need to use hibernate SQL or native SQL queries.

Related

Constructing a SQL save, update, remove query from hibernate entities?

Is it possible to create native SQL-queries for saving, updating or removing certain entities from the database via hibernate ?
What i am searching for is pretty much this...
String sqlQuery = session.save(listOfEntities);
session.execute(sqlQuery);
sqlQuery : "insert into players(id,...) values((10,...),(11,...))"
Why would you need the statements? Just doing session.persist(entity) will execute the statement for you already.

How to change order with TypedQuery in JPA

I wish to implement pagingation with FIQL support.
I am using apache cxf with JPA(Hibernate).
Here is sample example given for it http://cxf.apache.org/docs/jax-rs-search.html#JAX-RSSearch-JPA2.0
SearchConditionVisitor<Order, TypedQuery<Order>> visitor
= new JPATypedQueryVisitor<>(em, Order.class);
// connect FIQL cxf SearchCondition with our JPA visitor
searchCondition.accept(visitor);
// creeate JPA specific TypedQuery by our visitor
TypedQuery<Order> typedQuery = visitor.getQuery();
typedQuery.setFirstResult((page * perPage) - perPage);
typedQuery.setMaxResults(perPage);
// Run the query and return matching a complex FIQL criteria
return typedQuery.getResultList();
Every thing looks working including searching and pagination.
It looks have no order by clause being use from generate sql log and seems follow database insertion order.
Now I wish to change the default sorting order. For example I wish to sort by Order id field in descending order. How can I achieve that?
I can get it working with use of CriteriaQuery.
JPACriteriaQueryVisitor<Order, Order> jpa
= new JPACriteriaQueryVisitor<>(em, Order.class, Order.class);
searchCondition.accept(jpa);
CriteriaQuery<Order> cq = jpa.getCriteriaQuery();
CriteriaBuilder cb = em.getCriteriaBuilder();
Root<Order> root = (Root<Order>) cq.getRoots().iterator().next();
cq.orderBy(cb.desc(root.get("id")));
TypedQuery<Order> query = jpa.getTypedQuery();
query.setFirstResult((page * perPage) - perPage);
query.setMaxResults(perPage);
return query.getResultList();
You cannot change the order after creating the query.
If you use MySQL, then maybe you can use an integer parameter in ORDER BY :colnum DESC to specify the column number by which to sort (starting at 1 from the selected columns only), but you cannot change direction.
PostgreSQL does not allow you to do this. I do not know how it is on other databases, though. With MySQL, the parameters are replaced by the SQL Driver, so it always receives the full query with escaped sequences. With PG, the query is first parsed by the server, the execution plan is created (including if and how to order the results) and then the parameters are sent.

Criteria Query returnig all records

SQL :
String hql1 = "SELECT /* PARALLEL(MVR,16) PARALLEL(MVRS,16)*/ * FROM
ICM MINUS SELECT I1.* FROM ICM I1 , C1_ICM_STATIC I2 WHERE
I1.METRIC_DIRECTION=I2.METRIC_DIRECTION AND
I1.METRIC_NAME=I2.METRIC_NAME AND I1.METRIC_UNIT=I2.METRIC_UNIT AND
I1.TERMINATION_POINT_ID=I2.TERMINATION_POINT_ID AND
I1.TERMINATION_POINT_NAME=I2.TERMINATION_POINT_NAME AND
I1.TERMINATION_POINT_TYPE=I2.TERMINATION_POINT_TYPE";
Criteria Query
icms1 = (List<ICM>) session.createCriteria(ICM.class, hql1).list();
I have executed hql1 using SQL Developer then I got only one result, but when I have integrated SQL Query with Criteria it returning me all records in ICM table.
If SQL query returning only one result in SQL Developer, Why criteria API returning all records in ICM table?
Why criteria API returning all records in ICM table?
Technically you are not using criteria api for associations.
Try something like this.
Refer.
return criteria.createCriteria(A.class)
.createCriteria("b", "join_between_a_b")
.createCriteria("c", "join_between_b_c")
.createCriteria("d", "join_between_c_d")
.add(Restrictions.eq("some_field_of_D", someValue));
You should learn to read API documentation.
The second Session.createCriteria() argument is the alias that you want to assign to the root entity. It's not a HQL query. HQL queries are not executed using Session.createCriteria(). They're executed using Session.createQuery().
BTW, your query is not a HQL query at all. It's a SQL query. SQL and HQL are 2 different languages. To execute a SQL query, you need createSQLQuery().

Hibernate Criteria filter Entity where ManyToMany relation contains multiple objects

I need help with Hibernate Criteria API.
I have a class Job that contain a list of Skill in ManyToMany relationship.
I need to select jobs based on a skill list given as parameter.
I've tried with Restriction.in("skill.id",ids) but this gives me wrong list.If i've selected 2 skills in search form i want the jobs that contain BOTH of them,so i need somehow to implement AND clause.
I've tried with Conjunction:
Conjunction and = Restrictions.conjunction();
for(Skill skill:job.getSkills()){
and.add(Restrictions.eq("skill.id",skill.getId()));
}
And this:
Criteria crit = criteria.createCriteria("skills",JoinType.LEFT_OUTER_JOIN);
for(Skill skill:job.getSkills()){
crit.add(Restrictions.eq("id", skill.getId()));
}
but it creates same alias for skill and it gives me no result.
sql is and (skill1_.ID=? and skill1_.ID=?)
Can anyone help me with this ?thanks
UPDATE:
HQL Query will be like:
select a from Job a where exists (select skill1.id from Skill skill1 join skill1.jobs r where r.id=a.id and skill1.id=1) and exists (select skill2.id from Skill skill2 join skill2.jobs r where r.id=a.id and skill2.id=4)
I need Criteria based on this.
for(Skill skill:job.getSkills()){
DetachedCriteria subquery = DetachedCriteria.forClass(Skill.class,"skill");
subquery.add(Restrictions.eq("id",skill.getId()));
subquery.setProjection(Projections.property("id"));
subquery.createAlias("jobs", "job");
subquery.add(Restrictions.eqProperty("job.id", "Job.id"));
criteria.add(Subqueries.exists(subquery));
}
I managed to solve it.now it works perfect.

Automatic generation of java hibernate code from sql code

Is there a tool able to generate java hibernate code starting from the sql query?
(like reverse of what hibernate does, generating selects from java code) It will help me move all my queries to hibernate!
I mean if i have a select with parameters like this:
select ta.id label, ta.nume value
from ar
left outer join ta ta on idp = ta.ID
where ta.status = 1
and (dp = 0 OR ps = idps_)
and status = 1
order by ta.nume;
to obtain in the end something like this:
DetachedCriteria criteria = DetachedCriteria.forEntityName("ar");
criteria.createAlias("ta", "ta", Criteria.LEFT_JOIN);
criteria.add(Restrictions.eq("ta.status", 1));
Criterion eq = Restrictions.eq("ps.id", idps_);
Criterion isZero = Restrictions.eq("dp.id", 0);
Criterion or = Restrictions.or(eq, isZero);
criteria.add(or);
criteria.add(Restrictions.eq("status", 1));
ProjectionList projectionList = Projections.projectionList();
projectionList.add(Projections.property("ta.id"), "value");
projectionList.add(Projections.property("ta.nume"), "label");
criteria.setProjection(Projections.distinct(projectionList));
criteria.setResultTransformer(Transformers.ALIAS_TO_ENTITY_MAP);
criteria.addOrder(Order.asc("ta.nume"));
OR something similar using maps as output...
providing to the tool the path where i store the mappings of the entities/beans with the tables (or the path to the beans, if the beans are annotated)
You have the HQL that is an SQL-like dialect to work with Hibernate. You use field names from entities instead of those from tables. It supports joins etc.
In fact, Criteria API has very limited support of joins (at least it was so last time I've tried to used) and I've a few times finished rewriting everything from Criteria API to HQL, so I now simply tread Criteria API as no option.
In HQL you can also use SQL functions, both in SELECT and in WHERE part, those embedded and those you've written yourself.

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