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Jpa create native query from form input

Usually during my work hours i spend a lot of time querying the db(oracle) and parsing blob from various table where the streams that we receive are stored.
There are various type of stream so i was trying to made a simple webapp where i write the select statement and it returns all the stream parsed accordingly.
My problem is that using jpa and executing the simple native query:
select B_BODY from TABLE_B where TRANSACTION_ID = 'GG-148c-01502790743907855009';
the statement doesn't return anything but querying directly the database return the record.
this is my java code:
#Transactional(readOnly = true)
public List<Object[]> retrieveBlobs(String squery) {
squery = squery + " and rownum <= "+maxResults;
Query query = em.createNativeQuery(squery);
List<Object[]> resultList = query.getResultList();
return resultList;
}
this is the sql generated:
Hibernate:
select
B_BODY
from
TABLE_B
where
TRANSACTION_ID ='GG-148c-01502790743907855009'
and rownum <= 100
i know that this way might seems weird but our team spend a lot of time trying to tokenize the stored streams(the code that identify how to parse the stream is also stored in the tables).Useless to say this application is going to be used only internally.there is a way to just execute the query as it is and retrieve the correct output?

Well, I tried to reproduce your problem on MariaDB (with mysql-connector-java + hibernate) but selecting a lob with native query was working properly.
You can try to create entities which will be holding your blob and check if this would help. Just make a standard entity with #Lob annotation over your lob column.
#Entity
#NamedQueries(
#NamedQuery(name = FIND_ALL, query = "SELECT m FROM LobEntity m")
)
public class LobEntity {
public static final String FIND_ALL = "PhpEntity.findAll";
#Id
#Column(name = "id")
private String id;
#Lob
#Column(name = "lob")
private byte[] lob;
//Use Blob class if you want to use streams.
//#Column(name = "lob")
//#Lob
//private Blob lob;
}

How do I do a JPQL query with an underscore in the column name?

I am getting an error with the following JPQL query:
#NamedQuery (name = "Customer.getById", query =
"SELECT o
FROM bub.Customer o
WHERE o.user_id = :myid")
[bub.Customer is the #Entity name]
This is an excerpt of the error message I'm receiving:
org.hibernate.HibernateException:
Errors in named queries:
Customer.getById\n
Caused by: org.hibernate.HibernateException:
Errors in named queries: Customer.getById
When I remove the WHERE clause Wildfly allows me to deploy my web app so I know there is something wrong wtih my WHERE clause. Specifically since the column name is user_id in my Customer table I believe there may be an issue with the underscore(_) in the JPQL. I've tried changing the WHERE clause to "WHERE o.userId = :myid" but that didn't work either.
How can I fix the WHERE clause so my website will deploy and still work the correct way?
EDIT:
The relevant method is this:
public static Customer getById (final EntityManager em, final long id)
{
return em.createNamedQuery ("Customer.getById", Customer.class).setParameter ("myid", id).getSingleResult ();
}
I don't think this is the issue though.
EDIT2:
It turns out this was the issue:
#ManyToOne (fetch = FetchType.LAZY)
#JoinColumn (name = "user_id")
private User user;
I ended up changing the JPQL query to this and now it's working:
#NamedQuery (name = "Customer.getById", query =
"SELECT o
FROM bub.Customer o
WHERE o.user = :myid")

In JPQL you don't use the column name, but the attribute name(unless you annotate something else)

How to retrieve a member object of a class using Hibernate?

Using following code I can successfully retrieve address fields of a user, to do that I need to define all its fields using Projection. Imagine address has 100 fields, in this case I have to define all of them.
I am wondering if I can return just address object of customer without defining all its fields in Proposition?
I know I can retrieve id of address and use that to retrieve its object, but I am wondering if there is ano other method rather than this or defining all its fields.
Hibernate
.....
Criteria cre = session.createCriteria(User.class, "user")
.createAlias("user.address", "addr");
cre.add(Restrictions.eq("user.id", ID));
ProjectionList pl = Projections.projectionList();
pl.add(Projections.property("addr.id").as("id"));
pl.add(Projections.property("addr.unit").as("unit"));
.......
cre.setProjection(pl);
Address address = (Address) cre.list().get(0);
I used the following as well but it runs into error (could not resolve property: addr of: com.myProject.User)
pl.add(Projections.property("addr").as("address"));
Java
#Entity
public Class User {
#Id
#GeneratedValue
private long id;
#OneToOne
private Address address;
...
}

Use JPQL/HQL:
select a from User u join u.address a where u.id = :userId
The Criteria API is more limited than JPQL, and can't select any other entity than the root entity. It shouldn't be used if the query doesn't have to be dynamically composed. Of course, if the association is bidirectional, you can simply use
select a from Address a where a.user.id = :userId
or its equivalent Criteria:
Criteria c = session.createCriteria(Address.class, "a");
c.createAlias("a.user", "u");
c.add(Restrictions.eq("u.id", userId));

If the result you pull in from a query will match the fields of a DAO you have defined. I would just type-cast the result from an hql or native SQL query.
Select *
From Address a
where a.id = :userid
Address addrObject = (Address) query.uniqueResult();

Do like this
Criteria criteria = session.createCriteria(User.class, "user")
.createAlias("user.address", "addr")
.add(Restrictions.eq("user.id", userId))
.setProjection(Projections.property("addr"));
Address address = (Address) criteria.list().get(0);

Couple of options:
use lazy="false" for Address object. If you have to use lazy=true for some reason, you can run this query in a separate session and override the lazy behavior in that session.
Use the database specific query to get a list of field names and then dynamically generate Projections by looping through the field names.
For example,
In mysql
SHOW COLUMNS FROM Address
In postgres
SELECT * FROM information_schema.columns
WHERE table_schema = your_schema
AND table_name = your_table
I hope this helps.

hibernate HQL delete query nullifies single column

I am working on spring hibernate application and trying to delete from a table using non-id many-to-one relationship based column.
Entity classes are:
#Entity
public class Day {
#id(name = "DAY_ID")
dayId;
#OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY)
#JoinColumn(name = "DAY_ID")
List<Holiday> holidayList;
...
}
#Entity
public class Holiday {
#id(name="HOLIDAY_ID")
holidayId;
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "DAY_ID")
Day day;
...
}
I am trying to delete a row from holiday table using hql.
String query = "DELETE FROM Holiday WHERE day.dayId = " + dayObject.getdayId();
Query holidayDeleteQuery = getSession().createQuery(query);
holidayDeleteQuery.executeUpdate();
In the console i am getting proper delete query but on checking DB found out that the row is still there but now the DAY_ID column in holiday table is null. I am not able to figure out why is this happening?
EDIT: help!!! My main problem is why DAY_ID column is changing to null value??

I'm not sure that this is your problem, but in your query you say "DELETE FROM Holidays ...", but your Class name is Holiday. In HQL you should be using Class names rather than table names or anything else. Is this typo in your code or just on here?
Actually after looking further there are a few more problems. This is how I'd write it:
String query = "DELETE FROM Holiday h WHERE h.day = :day";
Query holidayDeleteQuery = getSession().createQuery(query);
query.setParameter("day", dayObject);
holidayDeleteQuery.executeUpdate();
To break it down - use the Class name "Holiday", assign it an alias "h" then reference the day field of the Holiday object ("h.day") and compare it to the actual Day object you have.

What is your ONDELETE foreign key constrain? Might it that other part of your application inserting a row?

Hibernate Criteria Api Subqueries

I am currently working on a project to transfer some legacy jdbc select statements over to using Hibernate and it's criteria api.
The two relevant table columns and the SQL query looks like:
-QUERIES-
primaryId
-QUERYDETAILS-
primaryId
linkedQueryId -> Foreign key references queries.primaryId
value1
value2
select *
from queries q
where q.primaryId not in (SELECT qd.linkedQueryId
FROM querydetails qd
WHERE (qd.value1 LIKE 'PROMPT%'
OR qd.value2 LIKE 'PROMPT%'));
My entity relationships look like:
#Table("queries")
public class QueryEntity{
#Id
#Column
private Long primaryId;
#OneToMany(targetEntity = QueryDetailEntity.class, mappedBy = "query", fetch = FetchType.EAGER)
private Set<QueryDetailEntities> queryDetails;
//..getters/setters..
}
#Entity
#Table(name = "queryDetails")
public class QueryDetailEntity {
#Id
#Column
private Long primaryId;
#ManyToOne(targetEntity = QueryEntity.class)
private QueryEntity query;
#Column(name="value1")
private String value1;
#Column(name="value2")
private String value2;
//..getters/setters..
}
I am attempting to utilize the criteria api in this way:
Criteria crit = sessionFactory.getCurrentSession().createCriteria(QueryEntity.class);
DetachedCriteria subQuery = DetachedCriteria.forClass(QueryDetailEntity.class);
LogicalExpression hasPrompt = Restrictions.or(Restrictions.ilike("value1", "PROMPT%"),
Restrictions.ilike("value2", "PROMPT%"));
subQuery.add(hasPrompt);
Criterion subQueryCrit = Subqueries.notIn("queryDetails", subQuery);
crit.add(subQueryCrit);
List<QueryMainEntity> entities = (List<QueryMainEntity>) crit.list();
System.out.println("# of results = " + entities.size());
I am getting a NullPointerException on the crit.list() line that looks like
Exception in thread "main" java.lang.NullPointerException
at org.hibernate.loader.criteria.CriteriaQueryTranslator.getProjectedTypes(CriteriaQueryTranslator.java:362)
at org.hibernate.criterion.SubqueryExpression.createAndSetInnerQuery(SubqueryExpression.java:153)
at org.hibernate.criterion.SubqueryExpression.toSqlString(SubqueryExpression.java:69)
at org.hibernate.loader.criteria.CriteriaQueryTranslator.getWhereCondition(CriteriaQueryTranslator.java:380)
at org.hibernate.loader.criteria.CriteriaJoinWalker.<init>(CriteriaJoinWalker.java:114)
at org.hibernate.loader.criteria.CriteriaJoinWalker.<init>(CriteriaJoinWalker.java:83)
at org.hibernate.loader.criteria.CriteriaLoader.<init>(CriteriaLoader.java:92)
at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1687)
at org.hibernate.impl.CriteriaImpl.list(CriteriaImpl.java:347)
Now, I think its pretty safe to say I'm using the Criteria Api/Detached Query Api incorrectly, but I'm not sure what the 'correct' way to do it is since the Hibernate Docs only briefly cover criteria api subqueries.
I realize this is a pretty long question, but I figure its appear to put it all the relevant aspects of the question (query I'm attempting to represent via Criteria API, tables, entities).

Give this a shot:
DetachedCriteria d = DetachedCriteria.forClass(QueryDetailEntity.class, "qd");
d.setProjection(Projections.projectionList().add(Projections.property("qd.query")));
d.add(Restrictions.or(Restrictions.like("qd.value1", "PROMPT%"), Restrictions.like("qd.value2", "PROMPT%")));
criteria = session.createCriteria(QueryEntity.class, "q");
criteria.add(Subqueries.propertyNotIn("q.primaryId", d));
criteria.list();
The use of the following are property names, not column names:
qd.query
qd.value1
qd.value2
q.primaryId
As a side note, if this is not a dynamically generated query, have you given thought to using HQL instead?