I am getting below mentioned error when trying to access records from DB using a spring-data-jpa and spring-data-rest.
Cannot create self link for class [Ljava.lang.Object;! No persistent
entity found!
I am using below query to retrieve information and my Class structure is somewhat as below
Agency
#OneToMany(mappedBy="agencyCode",cascade=CascadeType.ALL)
#JsonIgnore
List<Location> locations;
Location:
#ManyToMany
#JoinColumn(name = "zipCode")
Set<Zip> zips;
Zip:
#Id
#Column(name="zipCode")
String zipCode;
Query used to retrieve information is as below:
#Query("SELECT DISTINCT a, l.contactInfo.address.city, l.contactInfo.address.street, l.contactInfo.phone from Agency a, Location l INNER JOIN l.zips z where a.ceID = l.agencyCode and z.zipCode = :zip")
public List<Agency> findAgencyByZip(#Param("zip") String zip);
Any Help on this would be greatly appreciated.
Regards
Chetan
Don't know if this is the cause, but in Location, for #ManyToMany you need a #JoinTable instead of #JoinColumn. Fix that, and maybe this error will also be fixed. Try this:
#ManyToMany
#JoinTable(name = "LOCATION_ZIP", joinColumns = #JoinColumn(name = "LOCATION_LOC_CODE"),
inverseJoinColumns = #JoinColumn(name = "ZIPS_ZIP_CODE")
Set<Zip> zips;
Related
I have two entities connected bidirectional and I want to query the Location and its votes only for a specific date.
Location:
#Entity
#Table(name = "TAB_LOCATION")
#NamedQueries({
#NamedQuery(name = "Location.getVotedLocations", query = "SELECT l FROM Location l JOIN l.votes v WHERE v.location = l AND DATE(v.createdAt) = DATE(:date) ORDER BY l.name")
})
public class Location extends AbstractEntity {
#Basic
#Size(min = 5, max = 50)
private String name;
#Basic
#Size(min = 0, max = 50)
private String address;
#OneToMany(mappedBy = "location")
private Set<Vote> votes;
#Basic
private String description;
Vote:
#Entity
#Table(name = "TAB_VOTE")
public class Vote extends AbstractEntity {
#Basic
#ManyToOne
#NotNull
private User user;
#Basic
#ManyToOne
#NotNull
private Location location;
I was trying to use the named query but it seems that the Location always contains all votes regardless the condition.
Isn't it possible to map the queried values back to the object?
entityManager.createNamedQuery("Location.getVotedLocations").
setParameter("date", date).getResultList();
What is wrong?
If it isn't possible with NamedQueries, I also can use the Criteria API.
Here's a simple MySql statement that will return locationIDs not Location entity which are voted on a particular date.
Select DISTINCT LocationID FROM VOTE WHERE DATE == dateCreated;
And you can then get the Location entity by LocationID.
When you get an entity as a result from some query, you get the whole entity. It is not possible in JPA to get just a subset of all data, trimmed by where condition.
Well, if you use Hibernate, take a look at Hibernate Filters, with them you could get the result you want.
Note about your query, you have JOIN l.votes so you don't need to join it again with WHERE v.location = l.
I've tried to read through the QueryDSL docs but I am still very confused. I'm accustomed to writing a lot of SQL, but this is my first real crack at using QueryDSL w/ JPQL (JPA2).
I have the following entity:
#Entity
public class Provider implements Serializable {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "id")
private Long id;
#Version
#Column(name = "version")
private Integer version;
private String name;
#ManyToMany(cascade=CascadeType.ALL)
#JoinTable(name = "provider_contact", joinColumns = #JoinColumn(name = "contact_id", referencedColumnName = "id"), inverseJoinColumns = #JoinColumn(name = "provider_id", referencedColumnName = "id"))
#OrderColumn
private Collection<Contact> contact;
}
where Contact is a simple entity with an id for a pk.
#Entity
public class Contact {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "id")
private Long id;
/**
* User first name
*/
#NotNull
private String firstName;
/**
* User last name
*/
#NotNull
private String lastName;
}
I'm trying to write a query which returns a Contact object given a specific Contact.id and Provider.id. If the Contact object is not a part of the Provider's Contact collection, I'm looking for a null value.
I've tried the following:
public Contact getContact( long providerId, long contactId ){
Predicate p = QProvider.provider.id.eq(providerId).and(QContact.contact.id.eq(contactId));
JPQLQuery query = new JPAQuery(em);
return query.from(QProvider.provider).innerJoin(QProvider.provider.contact).where(p).singleResult(QContact.contact);
}
but I'm getting the following error:
Caused by: java.lang.IllegalArgumentException: Undeclared path 'contact'. Add this path as a source to the query to be able to reference it.
at com.mysema.query.types.ValidatingVisitor.visit(ValidatingVisitor.java:78)
at com.mysema.query.types.ValidatingVisitor.visit(ValidatingVisitor.java:30)
at com.mysema.query.types.PathImpl.accept(PathImpl.java:94)
I'm presuming it has something to do with the fact that my predicate references QContact.contact direction and not part of the QProvider.provider.contact object, but I'm really at a loss as to figure out how this should be done.
Am I even on the right track? I'm not even sure my join is correct either.
This should work
public Contact getContact(long providerId, long contactId) {
QProvider provider = QProvider.provider;
QContact contact = QContact.contact;
return new JPAQuery(em).from(provider)
.innerJoin(provider.contact, contact)
.where(provider.id.eq(providerId), contact.id.eq(contactId))
.singleResult(contact);
}
I have the following class:
#Entity
#Table(name = "entity")
public class Entity extends Model
{
#ManyToMany(fetch = FetchType.EAGER)
#JoinTable(name = "entity_owner", joinColumns = #JoinColumn(name = "entity_id"), inverseJoinColumns = #JoinColumn(name = "user_id"))
private Set<UserAccount> owners;
#ManyToMany(fetch = FetchType.EAGER)
#JoinTable(name = "entity_assignee", joinColumns = #JoinColumn(name = "entity_id"), inverseJoinColumns = #JoinColumn(name = "user_id"))
private Set<UserAccount> assignees;
}
I have a user account that I want to be able to being back all the Entity objects that have the user in either the owners or the assignees.
I tried this, which almost works, but seems to being back some sort of cartesian result:
String query = "SELECT r FROM models.Entity r LEFT JOIN r.assignees a LEFT JOIN r.owners n ";
query += "WHERE a.id = 1 OR n.id = 1";
Can anyone tell me what I am doing wrong?
If the UserAccount is in both owners and assignees, seems like the query will duplicate a result, you can use DISTINCT to filter duplicated results:
SELECT DISTINCT r FROM ...
When there is instance of UserAccount already available for filtering results,
MEMBER OF expression can be used:
SELECT DISTINCT(e)
FROM SomeEntity e
WHERE :someUser MEMBER OF e.assignees OR
:someUser MEMBER OF e.owners
UserAccount ua ...
em.createQuery(jpql).setParameter("someUser", ua)
If because of some reason query similar to original query is preferred, then adding DISTINCT is enough.
I want make a query where I join 2 tables, using the CriteriaBuilder. In MySQL the query I'm trying to make would look like this:
SELECT * FROM order
LEFT JOIN item
ON order.id = item.order_id
AND item.type_id = 1
I want to get all orders and if they have an item of type #1, I want to join with this item. However, if no item of type #1 is found, I still want to get the order. I can't figure out how to make this with the CriteriaBuilder. All I know how to make is:
CriteriaBuilder cb = em.getCriteriaBuilder();
CriteriaQuery<Order> cq = cb.createQuery(Order.class);
Root<Order> order = cq.from(Order.class);
Join<Order, Item> item = order.join(Order_.itemList, JoinType.LEFT);
Join<Item, Type> type = order.join(Item_.type, JoinType.LEFT);
cq.select(order);
cq.where(cb.equal(type.get(Type_.id), 1));
This query is broke, since it results in something like this in MySQL:
SELECT * FROM order
LEFT JOIN item
ON order.id = item.order_id
WHERE item.type_id = 1
The result will only contain orders with items of type #1. Orders without are excluded. How can I use the CriteriaBuilder to create a query like in the first example?
It is possible starting from the version 2.1 of JPA using the on method Join<Z, X> on(Predicate... restrictions);
Here is how:
Root<Order> order = cq.from(Order.class);
Join<Order, Item> item = order.join(Order_.itemList, JoinType.LEFT);
item.on(cb.equal(item.get(Item_.type), 1));
I think this is the same problem as posed in this question. It looks like it is not possible in CriteriaBuilder. It is possible in Hibernate Criteria API, but that probably won't help you.
JPA Criteria API: Multiple condition on LEFT JOIN
I know this question was made a long time a go, but recently a had the same problem and i found this solution from an Oracle forum, i copied and pasted just in case the link is not longer available.
MiguelChillitupaArmijos 29-abr-2011 1:41 (en respuesta a 840578) Think
you should use something like:
em.createQuery("SELECT DISTINCT e.Id" +
" from Email e " +
" left join e.idEmailIn e2 *with* e2.responseType = 'response'" +
" where e.type = 'in' and e.responseMandatory = true").getSingleResult();
An this is the link.
JPA Criteria : LEFT JOIN with an AND condition
There is a workaround if you are using Hibernate 3.6 with JPA 2.0
It is not the better solution, however it works perfect for me.
I´ve duplicate the entity with the #Where hibernate annotation.It means that everytime you use the join with this entity, hibernate will add the extra condition on the join statement at generated SQL.
For instance, initially we have the follow example:
#Entity
#Table(name = "PERSON")
public class Person {
#Id
#Column(name = "PERSON_ID")
private Long id;
#Id
#Column(name = "PERSON_NAME")
private String name;
#OneToMany(mappedBy = "person", fetch = FetchType.LAZY)
private Set<Address> addresses;
}
#Entity
#Table(name = "ADDRESS")
public class Address {
#Id
#Column(name = "ADDRESS_ID")
private Long id;
#Id
#Column(name = "ADDRESS_STREET")
private String street;
#ManyToOne
#JoinColumn(name = "PERSON_ID")
private Person person;
}
In order to add extra conditions on criteria Join, we need duplicate the Address #Entity mapping , adding the #Where annotation #Where(clause = " ADDRESS_TYPE_ID = 2").
#Entity
#Table(name = "ADDRESS")
#Where(clause = " ADDRESS_TYPE_ID = 2")
public class ShippingAddress {
#Id
#Column(name = "ADDRESS_ID")
private Long id;
#Id
#Column(name = "ADDRESS_STREET")
private String street;
#OneToOne
#JoinColumn(name = "PERSON_ID")
private Person person;
}
Also, we need to add the duplicate mapping association for the new entity.
#Entity
#Table(name = "PERSON")
public class Person {
#Id
#Column(name = "PERSON_ID")
private Long id;
#Id
#Column(name = "PERSON_NAME")
private String name;
#OneToMany(mappedBy = "person", fetch = FetchType.LAZY)
private Set<Address> addresses;
#OneToOne(mappedBy = "person")
private ShippingAddress shippingAddress;
}
Finally, you can use a join with this specific Entity in your criteria :
PersonRoot.join(Person_.shippingAddress, JoinType.LEFT);
The Hibernate Snippet SQL should seems like this :
left outer join
address shippingadd13_
on person11_.person_id=shippingadd13_.person_id
and (
shippingadd13_.ADDRESS_TYPE_ID = 2
)
ON clause is supported in Hibernate 4.3 version, anyone is aware if there is a parameter indexing issue between the parameter index of the additional custom conditions with the index of the existing mapping filters when doing an outer join with ON clause?
Using the Person entity class below as an example, say I am adding this filter to limit the address types and the filter is enabled to populate the IN clause. The parameter index for the IN clause will cause the issue [2] when I add additional conditions (such as using 'street' column) part of the ON clause. Is is a known issue?
[1] #Filter(name = "addressTypes", condition = "ADDRESS_TYPE in (:supportedTypes)")
[2]
Caused by: ERROR 22018: Invalid character string format for type BIGINT.
private Set addresses;
I am having a #ManyToMany mapping with #OrderColumn as follows:
class Tag {
#ManyToMany(fetch = FetchType.LAZY) #Getter
#JoinTable(
name = "tag_graph",
inverseJoinColumns = #JoinColumn(name = "parent_id"))
private Set<Tag> parents = new TreeSet<>();
#ManyToMany(fetch = FetchType.LAZY, mappedBy = "parents") #Getter #OrderColumn
private List<Tag> children = new ArrayList<>();
}
My problem is that I want to write an JPQL query which would use the #OrderColumn of the generated #JoinTable. Something like:
SELECT t FROM Tag t WHERE ... ORDER BY t.ORDER_COLUMN
Is there a way to do that?
You should be able to use the INDEX function in JPQL.
See,
http://en.wikibooks.org/wiki/Java_Persistence/JPQL#Special_Operators
There is no need to specify the order column in queries, it's automatically used behind the scenes to preserve the order in which elements have been added to the relationship list. For a better explanation you can refer to this link.