I am using springboot and springdata with Mysql.
I have 2 entities, Customer & Order:
#Entity
#Table(name = "customers")
public class Customer {
#Id
#GeneratedValue(strategy= GenerationType.IDENTITY)
#Column(name="id", nullable = false)
protected long id;
#Column(name = "name")
private String name;
}
#Entity
#Table(name = "orders")
public class Order {
#Id
#GeneratedValue(strategy= GenerationType.IDENTITY)
#Column(name="id", nullable = false)
protected long id;
#Column(name="customer_id")
private long customerId;
}
I also have a repository:
#Repository
public interface OrdersRepository extends JpaRepository<Order, Long> {
#Query("select o from Order o, Customer c where o.customerId = c.id")
Page<Order> searchOrders(final Pageable pageable);
}
The method has some more arguments for searching, but the problem is when I send a PageRequest object with sort that is a property of Customer.
e.g.
Sort sort = new Sort(Sort.Direction.ASC, "c.name");
ordersRepository.search(new PageRequest(x, y, sort));
However, sorting by a field of Order works well:
Sort sort = new Sort(Sort.Direction.ASC, "id");
ordersRepository.search(new PageRequest(x, y, sort));
The error I get is that c is not a property of Order (but since the query is a join of the entities I would expect it to work).
Caused by: org.hibernate.QueryException: could not resolve property c of Order
Do you have any idea how I can sort by a field of the joined entity?
Thank you
In JPA , the thing that you sort with must be something that is returned in the select statement, you can't sort with a property that is not returned
You got the error because the relationship is not modeled properly. In your case it is a ManyToOne relation. I can recomend the wikibooks to read further.
#Entity
#Table(name = "orders")
public class Order {
#Id
#GeneratedValue(strategy= GenerationType.IDENTITY)
#Column(name="id", nullable = false)
protected long id;
#ManyToOne
#JoinColumn(name="customer_id", referencedColumnName = "id")
private Customer customer;
}
The query is not needed anymore because the customer will be fetched.
#Repository
public interface OrdersRepository extends PagingAndSortingRepository<Order, Long> {
}
Now you can use nested properties.
Sort sort = new Sort(Sort.Direction.ASC, "customer.name");
ordersRepository.findAll(new PageRequest(x, y, sort));
Related
I have an issue trying to generate multiple relationship in JPA with three Entities.
Order
Product
Modifier
I have an Entity to handle the relationship many to many.
OrderProducts (order_id and product_id)
Contains the relationship of one order can have multiple products
OrderDetails (order_products_id and modifier_id)
Contains the id of the previous relationship Order-Products and the Id of the modifier which is a set of multiple values that can affect the price of the product.
Not quite sure how to handle this kind of relationship in JPA as I'm new to it.
You need a join entity with a composite key. You will need to research it further.
Your entities:
#Entity
#Table(name = "ordertable")
#Data
public class Order {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#OneToMany(mappedBy = "order")
#EqualsAndHashCode.Exclude
private Set<OrderProductModifier> products;
}
#Entity
#Table(name = "product")
#Data
public class Product {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#EqualsAndHashCode.Exclude
private BigDecimal unitPrice;
}
#Entity
#Table(name = "modifier")
#Data
public class Modifier {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#EqualsAndHashCode.Exclude
private BigDecimal modifier;
}
And the entity that ties it all together will need to have the foreign keys for each of the above entities, as you have noted.
#Entity
#Table(name = "orderproductmodifier")
#Data
public class OrderProductModifier {
#EmbeddedId
private OrderProductModifierId id;
#MapsId("orderId")
#ManyToOne
#EqualsAndHashCode.Exclude
#ToString.Exclude
private Order order;
#MapsId("productId")
#ManyToOne
#EqualsAndHashCode.Exclude
private Product product;
#MapsId("modifierId")
#ManyToOne
#EqualsAndHashCode.Exclude
private Modifier modifier;
}
#SuppressWarnings("serial")
#Embeddable
#Data
public class OrderProductModifierId implements Serializable {
private Long orderId;
private Long productId;
private Long modifierId;
}
This is pretty simple to use:
private void run() {
EntityManagerFactory factory = Persistence.createEntityManagerFactory("UsersDB");
EntityManager em = factory.createEntityManager();
em.getTransaction().begin();
Product product = new Product();
product.setUnitPrice(BigDecimal.TEN);
em.persist(product);
Modifier modifier = new Modifier();
modifier.setModifier(new BigDecimal(".90"));
em.persist(modifier);
Order order = new Order();
em.persist(order);
OrderProductModifier opm = new OrderProductModifier();
opm.setId(new OrderProductModifierId());
opm.setOrder(order);
opm.setProduct(product);
opm.setModifier(modifier);
em.persist(opm);
em.getTransaction().commit();
em.clear();
Order o = em.createQuery("select o from Order o join fetch o.products where o.id = 1", Order.class).getSingleResult();
System.out.println("Order for " + o.getProducts());
System.out.println("Order cost " + o.getProducts().stream().map(p->p.getProduct().getUnitPrice().multiply(p.getModifier().getModifier()).doubleValue()).collect(Collectors.summingDouble(Double::doubleValue)));
}
The above query could be better, but that will give you something to work on.
Getting below QueryExecutionRequestException when I try to excecute update Named query using JPA repository.
org.hibernate.hql.internal.QueryExecutionRequestException: Not supported for DML operations [update com.company.farmer.entity.FarmProducts p set p.isDeleted=:isDeleted where p.productId IN (:productIdsList_0, :productIdsList_1)]; nested exception is java.lang.IllegalStateException: org.hibernate.hql.internal.QueryExecutionRequestException: Not supported for DML operations [update com.company.farmer.entity.FarmProducts p set p.isDeleted=:isDeleted where p.productId IN (:productIdsList_0, :productIdsList_1)]
Code:
#Repository
public interface FarmProductRepository extends JpaRepository<FarmProducts, Long> {
void deleteProduct(#Param("isDeleted") String isDeleted, #Param("productIdsList") List<Long> productIdsList);
}
#Override
public String deleteProductAndCategory(long categoryId, FarmProductIdsDTO farmProductIds) {
farmProductRepository.deleteProduct(FarmerProductCategoryConstants.DELETE_YES_FLAG, farmProductIds.getFarmProductIds());
return FarmerProductCategoryConstants.SUCCESS;
}
#Entity
#Table(name="farm_products")
#Getter
#Setter
#ToString(exclude= "productCategory")
#NoArgsConstructor
#AllArgsConstructor
#NamedQueries({#NamedQuery(name="FarmProducts.deleteProduct", query="update FarmProducts p set p.isDeleted=:isDeleted where p.productId IN (:productIdsList)") })
public class FarmProducts extends BaseModel {
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "FARM_PRODUCT_GENERATOR")
#SequenceGenerator(name = "FARM_PRODUCT_GENERATOR", sequenceName = "FARM_PRODUCT_GENERATOR_SEQ", allocationSize = 1)
#Column(name = "farm_product_id")
public Long productId;
#ManyToOne
#JoinColumn(name = "farm_product_category_id")
#JsonIgnoreProperties("products")
public ProductCategory productCategory;
#Column(name = "product_name")
public String product;
#Column(name = "is_deleted")
public String isDeleted;
}
I am trying to pass a list of productId to make the isDeleted as "N". But update functionality fails because of the QueryExecutionRequestException.
By default Spring Data treats all queries as SELECT statements. If you have an UPDATE (or DELETE) statement you have you have to apply de #Modifying annotation on the query.
See https://docs.spring.io/spring-data/jpa/docs/current/reference/html/#jpa.modifying-queries
I have three database tables: Customer, Product and PurchaseOrder (for mapping). I am using openjpa for peristence in java rest application.
To all of the tables I have corresponding entities:
Customer
#Entity
#Table(name = "customer")
#XmlRootElement
#NamedQueries({...})
public class Customer implements Serializable {
...
#OneToMany(cascade = CascadeType.ALL, mappedBy = "customerId")
private Collection<PurchaseOrder> purchaseOrderCollection;
Product
#Entity
#Table(name = "product")
#XmlRootElement
#NamedQueries({...})
public class Product implements Serializable {
...
#OneToMany(cascade = CascadeType.ALL, mappedBy = "productId")
private Collection<PurchaseOrder> purchaseOrderCollection;
PurchaseOrder
#Entity
#Table(name = "purchase_order")
#XmlRootElement
#NamedQueries({..})
public class PurchaseOrder implements Serializable {
...
#Id
#Basic(optional = false)
#Column(name = "order_num")
private Integer orderNum;
#JoinColumn(name = "customer_id", referencedColumnName = "customer_id")
#ManyToOne(optional = false)
private Customer customer;
#JoinColumn(name = "product_id", referencedColumnName = "product_id")
#ManyToOne(optional = false)
private Product product;
What is the best way to get all the customers who ordered a product with specific id?
I could create namedQuery, I could build criteria with joins etc. But i think there could be a better way how to make use of the mapping entity (what would be point of this entity otherway?). Something like setting the productId to the purchaseOrder entity and then fetch all the customers via purchaseOrderCollection in customer entity? But i cannot figure it out. Is there other way than custom/named query or criteria building?
Thanks.
ok I figured it out, it can be this way
long productId = //get the id
Product product = entityManager.find(Product.class, productId);
Collection<PurchaseOrder> purchaseOrderCollection = product.getPurchaseOrderCollection();
if (purchaseOrderCollection != null) {
List<Integer> customers = new ArrayList<>(product.getPurchaseOrderCollection().size());
for (PurchaseOrder purchaseOrder : product.getPurchaseOrderCollection()) {
customers.add(purchaseOrder.getCustomerId());
}
return customers;
} else {
return Collections.EMPTY_LIST; // or null;
}
feel free to offer better sollution :)
I have the following entities and would like to seek help on how to query for selected attributes from both side of the relationship. Here is my model. Assume all tables are properly created in the db. JPA provider I am using is Hibernate.
#Entity
public class Book{
#Id
private long id;
#Column(nullable = false)
private String ISBNCode;
#ManyToOne(cascade = CascadeType.DETACH, fetch = FetchType.LAZY, optional = false)
private Person<Author> author;
#ManyToOne(cascade = CascadeType.DETACH, fetch = FetchType.LAZY, optional = true)
private Person<Borrower> borrower;
}
#Inheritance
#DiscriminatorColumn(name = "personType")
public abstract class Person<T>{
#Id
private long id;
#OneToOne(cascade = CascadeType.ALL, fetch = FetchType.EAGER)
private Info information;
}
#Entity
#DiscriminatorValue(PersonType.Author)
public class Author extends Person<Author> {
private long copiesSold;
}
#Entity
#DiscriminatorValue(PersonType.Borrower)
public class Borrower extends Person<Borrower> {
.....
}
#Entity
public class Info {
#Id
private long id;
#Column(nullable=false)
private String firstName;
#Column(nullable=false)
private String lastName;
......;
}
As you can see, the book table has a many to one relation to Person that is not nullable and Person that is nullable.
I have a requirement to show, the following in a tabular format -
ISBNCode - First Name - Last Name - Person Type
How can I write a JPA query that will allow me to select only attributes that I would want. I would want to get the attributes ISBN Code from Book, and then first and last names from the Info object that is related to Person Object that in turn is related to the Book object. I would not want to get all information from Info object, interested only selected information e.g first and last name in this case.
Please note that the relation between the Borrower and Book is marked with optional=true, meaning there may be a book that may not have been yet borrowed by someone (obviously it has an author).
Example to search for books by the author "Marc":
Criteria JPA Standard
CriteriaQuery<Book> criteria = builder.createQuery( Book.class );
Root<Book> personRoot = criteria.from( Book.class );
Predicate predicate = builder.conjunction();
List<Expression<Boolean>> expressions = predicate.getExpressions();
Path<Object> firtsName = personRoot.get("author").get("information").get("firstName");
expressions.add(builder.equal(firtsName, "Marc"));
criteria.where( predicate );
criteria.select(personRoot);
List<Book> books = em.createQuery( criteria ).getResultList();
Criteria JPA Hibernate
List<Book> books = (List<Book>)sess.createCriteria(Book.class).add( Restrictions.eq("author.information.firstName", "Marc") ).list();
We recommend using hibernate criterias for convenience and possibilities.
Regards,
I want to build the following pseudo query
Select a From APDU a where a.group.id= :id
group is a field in APDU class of the type APDUGroup.class.
I just want to get a list of APDUs based on APDUGroup's id.
How do i do that using a standard JPA query?
UPDATE
Yes, I have tried the above query and tried other variations for hours before posting in S/O. Here is the generated SQL for the query above:
SELECT t1.ID, t1.status, t1.type, t1.modified, t1.response, t1.expectedSize, t1.created, t1.description, t1.sequence, t1.name, t1.command, t1.recurring, t1.auth, t1.createdBy, t1.APDUGroup, t1.modifiedBy FROM APDUGroup t0, APDU t1 WHERE ((t0.ID = ?) AND (t0.ID = t1.APDUGroup))
The query looks okay but nothing get selected from my table.
There are at least 100 APDUs with APDUGroup = 1 in my test database.
I'm using eclipselink as the JPA provider.
Given the following Entities:
#Entity
public class APDU implements Serializable {
#Id
#GeneratedValue
private Long id;
#ManyToOne
private APDUGroup group;
//...
}
#Entity
public class APDUGroup implements Serializable {
#Id
#GeneratedValue
private Long id;
//...
}
The following query will return a list of APDUs for a given APDUGroup id:
select a from APDU a where a.group.id = :id
Oh, wait, that's your query :)
Entity 1:
#Entity
#Getter
#Setter
#Table(name = "invoices")
public class Invoice implements Serializable {
#Id
#GeneratedValue
#Column(name = "invoice_id", updatable = false, nullable = false)
private Long invoiceId;
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "person_id", referencedColumnName = "person_id", insertable = false, updatable = false, nullable = false)
private Person person;
//...
}
Entity 2:
#Entity
#Getter
#Setter
#Table(name = "people")
public class Person implements Serializable {
#Id
#GeneratedValue
#Column(name = "person_id", updatable = false, nullable = false)
private Long personId;
//...
}
Finally, Your Data Access Object (JPA Repository)
#Repository
public interface InvoiceRepository extends JpaRepository<Invoice, Long> {
#Query(value="SELECT x FROM Invoice x WHERE x.person.personId = :myPersonId")
List<Invoice> findInvoiceByPersonId (long myPersonId);
}
I hope this example has been helpful :)