I'm using the Spring PageRequest to sort (order) a custom query by a column in my database.
If I'm doing a custom query such as :
#Query( value = "select h from hunterhouse h join h.queens q where q.name = 'Computer Science'")
Is it not possible to sort by a column in q, the table I am joining to?
PageRequest request = new PageRequest(page, size, Sort.Direction.DESC, "q.region");
debug comes out as "order by h.q.region" which is incorrect, is it not possible to order by a join column?
You simply put the complete path you want to join on into the sort expression. So what you'd need to use is queens.region which will then be translated into h.queens.region and appended to the JPQL query you defined.
I had the same problem! This bug was fixed in Spring Data JPA 1.7.3 - just make sure you have a version higher or equal to 1.7.3! After that it will work with queens.region
Spring source: https://jira.spring.io/browse/DATAJPA-726
Related
I am trying to do the mappings and trying to write a non-native HQL query by joining the 4 tables. The logic is written in stored procedure, but we want to migrate it to hibernate/JPA. I am unable to do proper mappings and write a query to create same logic
FROM
[dbo].[vwInstitutionUser]AS IU
INNER JOIN [dbo].[vwCommonCourse] AS C
ON C.CustomerID=CAST(IU.InstitutionID AS VARCHAR(10))
INNER JOIN [dbo].[vwCommonCourses] AS CM
ON C.CourseID = CM.CourseID
INNER JOIN dbo.vwProductMaster AS PM
ON CM.LearningActivityID = PM.ResourceID
OR CM.AssessmentID = PM.AssessmentID
WHERE
IU.UserID = #UserID
AND PM.IsCert = CASE WHEN #SubReportID='MACS' THEN PM.IsCert ELSE
#IsCert END
ORDER BY PM.IsCert, PM.ResourceName
Please let me know if anybody has same use case, Thanks!
I m not sure if I undrestand you correctly, but i would recommend you the following actions:
Each inner join can be mapped as a relation within JPA (#OneToMany,
#OneToOne, #ManyToOne,#ManyToMany)
Ordering can be implemented with Comparable interface on entity level
For the computed values i would suggest to use sql computed value or service layer within your business logic which will provide you those values (#Transient field)
You can also write NativeQuery for you model
Hope that i answered at least some of your questions :)
I try to do the following inside a Spring Boot application : create a native query and page it so it can returns a page of a given number of elements from a #RestController.
Here's the snippet of my code, where em is the #PersistanceContext EntityManager, and the repository method is the following, knowing that queryString is the native query :
Query searchQuery = em.createNativeQuery(this.queryString, MyEntity.class);
List<MyEntity> resultsList = searchQuery.getResultList();
return new PageImpl<>(resultsList, PageRequest.of(index,size), resultsList.size());
My problem is that the Page returned has a content of the complete query result, not a content of the size of size parameter inside the PageRequest.of.
Has anybody faced the same issue and could give a working example on how to paginate a nativeQuery please ?
Thanks for your help
You are mixing Spring Data JPA (Pageable) with JPA EntityManager. You can't do that. If you are already using a native query then simply put the pagination in the query. You can use what your database supports, for example the standard:
SELECT [a_bunch_of_columns]
FROM dbo.[some_table]
ORDER BY [some_column_or_columns]
OFFSET #PageSize * (#PageNumber - 1) ROWS
FETCH NEXT #PageSize ROWS ONLY;
this is example of using native query with pagination:
#Query("SELECT c FROM Customer As c INNER JOIN Offer as f on f.id=c.specialOffer.id inner join User As u on u.id=f.user.id where u.id=?1 And c.status=?2")
Page<Customer> getAllCustomerToShop(Integer shopId,String status,Pageable pageable)
and then you can call it as:
getAllCustomerToShop(shopId,"status",PageRequest.of(index, PAGE_SIZE));
Modify your code as follows
Query searchQuery = em.createNativeQuery(this.queryString, MyEntity.class)
.setFirstResult(pageable.getPageNumber() * pageable.getPageSize())
.setMaxResults(pageable.getPageSize());
My Spring data JPA code to get the data from db based on some search criteria is not working. My DB is SQL Server 2012, same query seem to work with MYSQL DB.
Code Example :
#Query(value = "select * from entity e where e.emp_id=:#{#mySearchCriteria.empId} and ((:#{#mySearchCriteria.deptIds} is null or :#{#mySearchCriteria.deptIds} ='') or e.dept_id in (:#{#mySearchCriteria.deptIds})) ", nativeQuery = true)
public List<Entity> search(#Param("mySearchCriteria") MySearchCriteria mySearchCriteria);
if list mySearchCriteria.deptIds has more than one value- it's not working(it's actually translating it to wrong query. Any lead? Thanks in advance.
Note: data type for deptIds is List of Integer
Its complaining because values of {#mySearchCriteria.deptIds} is comma separated list e.g. 'Value1', 'Value2' so the query gets translated as ('Value1', 'Value2' is null) which causes this error.
Need to verify if list is empty or not and then change the query with IN clause and one without IN clause.
Surround the list by parentheses. This works for me.
(:#{#mySearchCriteria.deptIds}) is null
I am trying to fetch the employee details whose empltype is clerk and whose joining date is the recent one.
For which the query looks like following in SQL Server 2008:
select
*
from
employee jj
inner join
(
select
max(join_date) as jdate,
empltype as emptype
from
employee
where
empltype='clerk'
group by empltype
) mm
on jj.join_date=mm.jdate and jj.empltype=mm.emptype;
I am using SpringData JPA as my persistence layer using QuerylDSL,Specification and Predicate to fetch the data.
I am trying to convert the above query either in QueryDSL or Specification, but unable to hook them properly.
Employee Entity :
int seqid;(sequence id)
String empltype:
Date joindate;
String role;
Predicate method in Specifcation Class :
Predicate toPredicate(Root<employee> root,CriteriaQuery <?> query,CriteriaBuilder cb)
{
Predicate pred=null;
// Returning the rows matching the joining date
pred=cb.equal(root<Emplyoee_>.get("joindate"));
//**//
}
What piece of code should be written in //**// to convert about SQL query to JPA predicate. any other Spring Data JPA impl like #Query,NamedQuery or QueryDSL which returns Page also works for me.
Thanks in advance
I wrote this in notepad and it hasn't been tested but I think you're looking for something like
QEmployee e1 = new QEmployee("e1");
QEmployee e2 = new QEmployee("e2");
PathBuilder<Object[]> eAlias = new PathBuilder<Object[]>(Object[].class, "eAlias");
JPASubQuery subQuery = JPASubQuery().from(e2)
.groupBy(e2.empltype)
.where(e2.empltype.eq('clerk'))
.list(e2.join_date.max().as("jdate"), e2.emptype)
jpaQuery.from(e1)
.innerJoin(subQuery, eAlias)
.on(e1.join_date.eq(eAlias.get("jdate")), e1.emptype.eq(eAlias.get("emptype")))
.list(qEmployee);
I have the following HQL in Hibernate using Spring MVC.
List<Colour>list=session.createQuery("from Colour order by colourId desc")
.setFirstResult((currentPage-1)*rowsPerPage)
.setMaxResults(rowsPerPage).list();
It works and returns a list of rows from the colour table (actually operates upon the Colour entity (POJO) that I can understand) in Oracle 10g.
What if I need to retrieve a list fields, I'm trying the following.
List<Colour>list=session.createQuery("colourId, colourName, colourHex from Colour order by colourId desc")
.setFirstResult((currentPage-1)*rowsPerPage)
.setMaxResults(rowsPerPage).list();
It ends with an excpetion
java.lang.IllegalArgumentException: node to traverse cannot be null!
In some articles, it was mentioned that the following version of HQL should (or may) work
List<Colour>list=session.createQuery("select colourId, colourName, colourHex from Colour order by colourId desc")
.setFirstResult((currentPage-1)*rowsPerPage)
.setMaxResults(rowsPerPage).list();
but unfortunately, it also didn't work for me. Using the createSQLQuery() method to execute native SQL would work but I want to stick to the createQuery() method with HQL unless it's absolutely necessary. How can I specify a list of fields in HQL?
I agree with yorkw's comment. If you select properties in your query then you cannot ask for a List<Colour> object to be returned from a call to .list().
Instead you should do this
List<Object[]> rows = session.createQuery("select c.colourId, c.colourName, c.colourHex " +
" from Colour c " +
" order by c.colourId desc").list();
Then iterate over the list object and instantiate your objects. Or whatever you need to do.
for ( Object[] row : rows ) {
Long colourId = (Long)row[0];
// ... etc
}
Why don't you try creating a map? Something like this:
SELECT NEW MAP( colour.colourId AS id
, colour.colourName AS name ...)
FROM Colour colour
ORDER BY colour.colourId
I use the alias for Colour "colour" so hibernate knows from which entity is the property I am referencing, I am implying all those properties are from the same entity, if not, then check your referencing!