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JPA createQuery where condition does not work

I am trying to use JPA to fetch records from database. However I am able to insert records indatabse and even get all the records using createQuery method of class EntityManager.
But in below case I am not getting why the condition in where clause is not working.
Please help me figure it out.
POJO class :
#Entity
#Table(name = "frameworks_filter")
public class FilteredFrameworksDbStructure {
#Id
#Column(name="id")
#GeneratedValue(strategy = GenerationType.IDENTITY)
private int id;
#Column(name = "regular_name")
private String regularName;
#Column(name = "component_name")
private String componentName;
#Column(name = "component_owner")
private String componentOwner;
#Column(name = "frameworks")
private String frameworks;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getRegularName() {
return regularName;
}
public void setRegularName(String regularName) {
this.regularName = regularName;
}
public String getComponentName() {
return componentName;
}
public void setComponentName(String componentName) {
this.componentName = componentName;
}
public String getComponentOwner() {
return componentOwner;
}
public void setComponentOwner(String componentOwner) {
this.componentOwner = componentOwner;
}
public String getFrameworks() {
return frameworks;
}
public void setFrameworks(String frameworks) {
this.frameworks = frameworks;
}
}
DAO class method:
public List<FilteredFrameworksDbStructure> getFilteredFrameworks(String regularName) {
EntityManager entityManager = entityManagerFactory.createEntityManager();
List<FilteredFrameworksDbStructure> filteredFrameworksDbStructureList = entityManager
.createQuery("from FilteredFrameworksDbStructure F where F.regularName = :regular", FilteredFrameworksDbStructure.class)
.setParameter("regular", regularName)
.getResultList();
return filteredFrameworksDbStructureList;
}
Issue : Condition in where clause does not work. It simply fetch all the records irrespective of the regularName provided.
Regards,
Parag Vinchurkar

Why don't you use the JpaRepository or CrudRepository to fetch your results? Check out this tutorial here and here on how to use them.
And you can use your where clause. Please see below the example repository you can use to obtain the same results as the entityManager
public interface FilteredFrameworksDbStructureRepo extends JpaRepository<FilteredFrameworksDbStructure , Integer>{
List<FilteredFrameworksDbStructure> findAllByRegularName(String regularName)
}
Please note that you will have to change your id member variable from int to Integer

jpa composite primary key table not returning values

I am new JPA and I am facing exceptions when I retrieve the values from composite primiary key table.
Exception Description:
Problem compiling [select t from ASSIGN_TASK_EMPLOYEE t].
[14, 34] The abstract schema type 'ASSIGN_TASK_EMPLOYEE' is unknown.
at org.eclipse.persistence.internal.jpa.EntityManagerImpl.createQuery(EntityManagerImpl.java:1605)
Following are my code
#Entity
#Table(name = "ASSIGN_TASK_EMPLOYEE")
//#IdClass(AssignTaskEmployeePk.class)
public class AssignTaskEmployee implements Serializable {
#EmbeddedId
private AssignTaskEmployeePk assignTaskEmployeePk;
public AssignTaskEmployeePk getAssignTaskEmployeePk() {
return assignTaskEmployeePk;
}
public void setAssignTaskEmployeePk(AssignTaskEmployeePk assignTaskEmployeePk) {
this.assignTaskEmployeePk = assignTaskEmployeePk;
}
}
#Embeddable
public class AssignTaskEmployeePk {
private String employeeId;
private String taskId;
public AssignTaskEmployeePk() {
}
#Override
public boolean equals(Object obj) {
// TODO Auto-generated method stub
if (obj instanceof AssignTaskEmployeePk) {
AssignTaskEmployeePk employeePk = (AssignTaskEmployeePk) obj;
if (!employeePk.getEmployeeId().equals(this.employeeId)) {
return false;
}
else if (!employeePk.getTaskId().equals(this.taskId)) {
return false;
}
}
else {
return false;
}
return false;
}
#Override
public int hashCode() {
return employeeId.hashCode() + taskId.hashCode() ;
}
public String getEmployeeId() {
return employeeId;
}
public void setEmployeeId(String employeeId) {
this.employeeId = employeeId;
}
public String getTaskId() {
return taskId;
}
public void setTaskId(String taskId) {
this.taskId = taskId;
}
}
I have added four values in the databases for composite primary key ASSIGN_TASK_EMPLOYEE (table) which PK table
EMP_ID TASKID
1 2
2 4
3 5
4 6
Now I would like to get the tasks assigned to emp_id 1
For that I wrote the query below:This would supposed to return list of AssignTaskEmployee object.
entityManager.createQuery("select t from ASSIGN_TASK_EMPLOYEE t").getResultList()
When I execute this query, I am getting the following exception
Exception Description:
Problem compiling [select t from ASSIGN_TASK_EMPLOYEE t].
[14, 34] The abstract schema type 'ASSIGN_TASK_EMPLOYEE' is unknown.
at org.eclipse.persistence.internal.jpa.EntityManagerImpl.createQuery(EntityManagerImpl.java:1605)

JPQL should use entities names, default are the name of the class. AssignTaskEmployee
It should be
entityManager.createQuery("select t from AssignTaskEmployee t").getResultList()
The above will be return all the records in table ASSIGN_TASK_EMPLOYEE.
If you want to retrieve a specific record with JPQL you should use WHERE statement as it follows:
Query query = entityManager.createQuery("select t from AssignTaskEmployee t WHERE
t.assignTaskEmployeePk.employeeId = :employeeId and t.assignTaskEmployeePk.taskId = :taskId")
query.setParameter("employeeId", 1);
query.setParameter("taskId",1);
query.getSingleResult() //As expected to have only one record.
Read this to query over EmbeddedId

Is it possible to use raw SQL within a Spring Repository

I need to use raw SQL within a Spring Data Repository, is this possible? Everything I see around #Query is always entity based.

The #Query annotation allows to execute native queries by setting the nativeQuery flag to true.
Quote from Spring Data JPA reference docs.
Also, see this section on how to do it with a named native query.

YES, You can do this in bellow ways:
1. By CrudRepository (Projection)
Spring Data Repositories usually return the domain model when using query methods. However, sometimes, you may need to alter the view of that model for various reasons.
Suppose your entity is like this :
import javax.persistence.*;
import java.math.BigDecimal;
#Entity
#Table(name = "USER_INFO_TEST")
public class UserInfoTest {
private int id;
private String name;
private String rollNo;
public UserInfoTest() {
}
public UserInfoTest(int id, String name) {
this.id = id;
this.name = name;
}
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "ID", nullable = false, precision = 0)
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
#Basic
#Column(name = "name", nullable = true)
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
#Basic
#Column(name = "roll_no", nullable = true)
public String getRollNo() {
return rollNo;
}
public void setRollNo(String rollNo) {
this.rollNo = rollNo;
}
}
Now your Projection class is like below. It can those fields that you needed.
public interface IUserProjection {
int getId();
String getName();
String getRollNo();
}
And Your Data Access Object(Dao) is like bellow :
import org.springframework.data.jpa.repository.Query;
import org.springframework.data.repository.CrudRepository;
import java.util.ArrayList;
public interface UserInfoTestDao extends CrudRepository<UserInfoTest,Integer> {
#Query(value = "select id,name,roll_no from USER_INFO_TEST where rollNo = ?1", nativeQuery = true)
ArrayList<IUserProjection> findUserUsingRollNo(String rollNo);
}
Now ArrayList<IUserProjection> findUserUsingRollNo(String rollNo) will give you the list of user.
2. Using EntityManager
Suppose your query is "select id,name from users where roll_no = 1001".
Here query will return an object with id and name column. Your Response class is like bellow:
Your Response class is like this:
public class UserObject{
int id;
String name;
String rollNo;
public UserObject(Object[] columns) {
this.id = (columns[0] != null)?((BigDecimal)columns[0]).intValue():0;
this.name = (String) columns[1];
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getRollNo() {
return rollNo;
}
public void setRollNo(String rollNo) {
this.rollNo = rollNo;
}
}
here UserObject constructor will get an Object Array and set data with the object.
public UserObject(Object[] columns) {
this.id = (columns[0] != null)?((BigDecimal)columns[0]).intValue():0;
this.name = (String) columns[1];
}
Your query executing function is like bellow :
public UserObject getUserByRoll(EntityManager entityManager,String rollNo) {
String queryStr = "select id,name from users where roll_no = ?1";
try {
Query query = entityManager.createNativeQuery(queryStr);
query.setParameter(1, rollNo);
return new UserObject((Object[]) query.getSingleResult());
} catch (Exception e) {
e.printStackTrace();
throw e;
}
}
Here you have to import bellow packages:
import javax.persistence.Query;
import javax.persistence.EntityManager;
Now your main class, you have to call this function. First get EntityManager and call this getUserByRoll(EntityManager entityManager,String rollNo) function. The calling procedure is given below:
Here is the Imports
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
get EntityManager from this way:
#PersistenceContext
private EntityManager entityManager;
UserObject userObject = getUserByRoll(entityManager,"1001");
Now you have data in this userObject.
Note:
query.getSingleResult() return a object array. You have to maintain the column position and data type with the query column position.
select id,name from users where roll_no = 1001
query return a array and it's [0] --> id and [1] -> name.
More info visit this thread and this Thread
Thanks :)

It is possible to use raw query within a Spring Repository.
#Query(value = "SELECT A.IS_MUTUAL_AID FROM planex AS A
INNER JOIN planex_rel AS B ON A.PLANEX_ID=B.PLANEX_ID
WHERE B.GOOD_ID = :goodId",nativeQuery = true)
Boolean mutualAidFlag(#Param("goodId")Integer goodId);

we can use createNativeQuery("Here Native SQL Query ");
for Example :
Query q = em.createNativeQuery("SELECT a.firstname, a.lastname FROM Author a");
List<Object[]> authors = q.getResultList();

This is how you can use in simple form
#RestController
public class PlaceAPIController {
#Autowired
private EntityManager entityManager;
#RequestMapping(value = "/api/places", method = RequestMethod.GET)
public List<Place> getPlaces() {
List<Place> results = entityManager.createNativeQuery("SELECT * FROM places p limit 10").getResultList();
return results;
}
}

It is also possible to use Spring Data JDBC, which is a fully supported Spring project built on top of Spring Data Commons to access to databases with raw SQL, without using JPA.
It is less powerful than Spring Data JPA, but if you want lightweight solution for simple projects without using a an ORM like Hibernate, that a solution worth to try.

avoiding distinct keyword in batch query

Using Eclipselink 2.4.1, I'm trying to avoid the "distinct" keyword from appearing in batch queries. Documentation suggests that when using batch type EXISTS the distinct keyword isn't used, however in my experience it's used in all cases when retrieving a many-to-one relationship. For example, I have the following classes written against the SCOTT demo schema in oracle:
#Entity
public class Emp implements Serializable {
#Id private long empno;
private String ename;
#ManyToOne
#JoinColumn(name="DEPTNO")
private Dept dept;
public Emp() { }
public long getEmpno() { return this.empno; }
public void setEmpno(long empno) { this.empno = empno; }
public String getEname() { return this.ename; }
public void setEname(String ename) { this.ename = ename; }
public Dept getDept() { return this.dept; }
public void setDept(Dept dept) { this.dept = dept; }
}
#Entity
public class Dept implements Serializable {
#Id private long deptno;
private String dname;
public Dept() {}
public long getDeptno() { return this.deptno; }
public void setDeptno(long deptno) { this.deptno = deptno; }
public String getDname() { return this.dname; }
public void setDname(String dname) { this.dname = dname; }
}
I'm attempting to retrieve the employees and departments via batch fetch:
Query query = em.createQuery("select emp from Emp as emp ");
query.setHint(QueryHints.BATCH_TYPE, BatchFetchType.EXISTS);
query.setHint(QueryHints.BATCH, "emp.dept");
List<Emp> resultList = query.getResultList();
resultList.get(0).getDept();
The following SQL is generated:
[EL Fine]: sql: 2012-12-12 17:04:21.178--ServerSession(1034011695)--Connection(312759349)--SELECT EMPNO, ENAME, DEPTNO FROM SCOTT.EMP
[EL Fine]: sql: 2012-12-12 17:04:21.286--ServerSession(1034011695)--Connection(312759349)--SELECT distinct t0.DEPTNO, t0.DNAME FROM SCOTT.DEPT t0 WHERE EXISTS (SELECT t1.EMPNO FROM SCOTT.EMP t1 WHERE (t0.DEPTNO = t1.DEPTNO))
Is there something additional that needs to be done in addition to using EXISTS batch type to avoid the distinct keyword in batch queries?

Please log a bug. It should only be using this for JOIN batching.
You can set distinct to false on the query to avoid it. (there is no hint, you need to call dontUseDistinct() on the root ObjectLevelReadQuery).
((ObjectLevelReadQuery)((JpaQuery)query).getDatabaseQuery()).dontUseDistinct();

use of entityManager.createNativeQuery(query,foo.class)

I would like to return a List of Integers from a
javax.persistence.EntityManager.createNativeQuery call
Why is the following incorrect?
entityManager.createNativeQuery("Select P.AppID From P", Integer.class);
specifically why do I get "...Unknown entity: java.lang.Integer"
Would I have to create an entity class that has a single field that is an Integer ?
Thanks

What you do is called a projection. That's when you return only a scalar value that belongs to one entity. You can do this with JPA. See scalar value.
I think in this case, omitting the entity type altogether is possible:
Query query = em.createNativeQuery( "select id from users where username = ?");
query.setParameter(1, "lt");
BigDecimal val = (BigDecimal) query.getSingleResult();
Example taken from here.

That doesn't work because the second parameter should be a mapped entity and of course Integer is not a persistent class (since it doesn't have the #Entity annotation on it).
for you you should do the following:
Query q = em.createNativeQuery("select id from users where username = :username");
q.setParameter("username", "lt");
List<BigDecimal> values = q.getResultList();
or if you want to use HQL you can do something like this:
Query q = em.createQuery("select new Integer(id) from users where username = :username");
q.setParameter("username", "lt");
List<Integer> values = q.getResultList();
Regards.

Here is a DB2 Stored Procidure that receive a parameter
SQL
CREATE PROCEDURE getStateByName (IN StateName VARCHAR(128))
DYNAMIC RESULT SETS 1
P1: BEGIN
-- Declare cursor
DECLARE State_Cursor CURSOR WITH RETURN for
-- #######################################################################
-- # Replace the SQL statement with your statement.
-- # Note: Be sure to end statements with the terminator character (usually ';')
-- #
-- # The example SQL statement SELECT NAME FROM SYSIBM.SYSTABLES
-- # returns all names from SYSIBM.SYSTABLES.
-- ######################################################################
SELECT * FROM COUNTRY.STATE
WHERE PROVINCE_NAME LIKE UPPER(stateName);
-- Cursor left open for client application
OPEN Province_Cursor;
END P1
Java
//Country is a db2 scheme
//Now here is a java Entity bean Method
public List<Province> getStateByName(String stateName) throws Exception {
EntityManager em = this.em;
List<State> states= null;
try {
Query query = em.createNativeQuery("call NGB.getStateByName(?1)", Province.class);
query.setParameter(1, provinceName);
states= (List<Province>) query.getResultList();
} catch (Exception ex) {
throw ex;
}
return states;
}

Suppose your query is "select id,name from users where rollNo = 1001".
Here query will return a object with id and name column.
Your Response class is like bellow:
public class UserObject{
int id;
String name;
String rollNo;
public UserObject(Object[] columns) {
this.id = (columns[0] != null)?((BigDecimal)columns[0]).intValue():0;
this.name = (String) columns[1];
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getRollNo() {
return rollNo;
}
public void setRollNo(String rollNo) {
this.rollNo = rollNo;
}
}
here UserObject constructor will get a Object Array and set data with object.
public UserObject(Object[] columns) {
this.id = (columns[0] != null)?((BigDecimal)columns[0]).intValue():0;
this.name = (String) columns[1];
}
Your query executing function is like bellow :
public UserObject getUserByRoll(EntityManager entityManager,String rollNo) {
String queryStr = "select id,name from users where rollNo = ?1";
try {
Query query = entityManager.createNativeQuery(queryStr);
query.setParameter(1, rollNo);
return new UserObject((Object[]) query.getSingleResult());
} catch (Exception e) {
e.printStackTrace();
throw e;
}
}
Here you have to import bellow packages:
import javax.persistence.Query;
import javax.persistence.EntityManager;
Now your main class, you have to call this function.
First you have to get EntityManager and call this getUserByRoll(EntityManager entityManager,String rollNo) function. Calling procedure is given bellow:
#PersistenceContext
private EntityManager entityManager;
UserObject userObject = getUserByRoll(entityManager,"1001");
Now you have data in this userObject.
Here is Imports
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
Note:
query.getSingleResult() return a array. You have to maintain the column position and data type.
select id,name from users where rollNo = ?1
query return a array and it's [0] --> id and [1] -> name.
For more info, visit this Answer
Thanks :)

JPA was designed to provide an automatic mapping between Objects and a relational database. Since Integer is not a persistant entity, why do you need to use JPA ? A simple JDBC request will work fine.