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How to write this query in HQL?

I'm learning Hibernate and I'm having trouble writing queries against many-to-many tables. I need to translate this into the HQL
SELECT books.id,books.name,books.year,books.priceRent,books.priceSell,books.amount, author.full_name,genre.genre_name FROM books
INNER JOIN book_author ON books.id = book_author.book_id
INNER JOIN author ON book_author.author_id = author.author_id
INNER JOIN book_genre ON books.id = book_genre.genre_id
INNER JOIN genre ON book_genre.genre_id = genre.genre_id
I tried to write like this:
FROM Book b LEFT JOIN b.author LEFT JOIN b.genre
But it gives an error:
java.sql.SQLSyntaxErrorException: Unknown column 'genre3_.id' in 'on clause'
At the same time, I already have all the table entities
Here is Author Entity
#Entity
#Table(name = "author")
public class Author {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "author_id")
private Integer id;
#Column(name = "full_name")
private String name;
public Author(String name) {
this.name = name;
}
public Author() {
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public List<Book> getBookList() {
return bookList;
}
public void setBookList(List<Book> bookList) {
this.bookList = bookList;
}
#ManyToMany(cascade = {CascadeType.PERSIST,CascadeType.MERGE,CascadeType.DETACH,CascadeType.REFRESH})
#JoinTable(name = "book_author",joinColumns = #JoinColumn(name = "author_id"),inverseJoinColumns = #JoinColumn(name = "book_id"))
private List<Book> bookList;
#Override
public String toString() {
return "Author{" +
"id=" + id +
", name='" + name + '\'' +
'}';
}
}
Here is Genre Entity
#Entity
#Table(name = "genre")
public class Genre {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "genre_id")
private Integer id;
#Column(name = "genre_name")
private String genre;
#ManyToMany(cascade = {CascadeType.PERSIST,CascadeType.MERGE,CascadeType.DETACH,CascadeType.REFRESH})
#JoinTable(name = "book_genre",joinColumns = #JoinColumn(name = "genre_id"),inverseJoinColumns = #JoinColumn(name = "book_id"))
private List<Book> bookList;
public Genre(){}
public List<Book> getBookList() {
return bookList;
}
public void setBookList(List<Book> bookList) {
this.bookList = bookList;
}
public Genre(String genre) {
this.genre = genre;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getGenre() {
return genre;
}
public void setGenre(String genre) {
this.genre = genre;
}
#Override
public String toString() {
return "Genre{" +
"id=" + id +
", genre='" + genre + '\'' +
'}';
}
}
Here is Book Entity
#Entity
#Table(name = "books")
public class Book {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "id")
private Integer id;
#Column(name = "name")
private String name;
#Column(name = "year")
private String year;
#Column(name = "priceRent")
private Integer priceRent;
#Column(name = "priceSell")
private Integer priceSell;
#Column(name = "amount")
private Integer amount;
#ManyToMany(cascade = {CascadeType.PERSIST,CascadeType.MERGE,CascadeType.DETACH,CascadeType.REFRESH})
#JoinTable(name = "book_author",
joinColumns = #JoinColumn(name = "id"),
inverseJoinColumns = #JoinColumn(name = "author_id"))
private List<Author> authorList;
#ManyToMany(cascade = {CascadeType.PERSIST,CascadeType.MERGE,CascadeType.DETACH,CascadeType.REFRESH})
#JoinTable(name = "book_genre",
joinColumns = #JoinColumn(name = "id"),
inverseJoinColumns = #JoinColumn(name = "genre_id"))
private List<Genre> genreList;
public Book() {
}
public Book(String name, String year, Integer priceRent, Integer priceSell, Integer amount) {
this.name = name;
this.year = year;
this.priceRent = priceRent;
this.priceSell = priceSell;
this.amount = amount;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getYear() {
return year;
}
public void setYear(String year) {
this.year = year;
}
public Integer getPriceRent() {
return priceRent;
}
public void setPriceRent(Integer priceRent) {
this.priceRent = priceRent;
}
public Integer getPriceSell() {
return priceSell;
}
public void setPriceSell(Integer priceSell) {
this.priceSell = priceSell;
}
public Integer getAmount() {
return amount;
}
public void setAmount(Integer amount) {
this.amount = amount;
}
public List<Author> getAuthorList() {
return authorList;
}
public void setAuthorList(List<Author> authorList) {
this.authorList = authorList;
}
public List<Genre> getGenreList() {
return genreList;
}
public void setGenreList(List<Genre> genreList) {
this.genreList = genreList;
}
#Override
public String toString() {
return "Book{" +
"id=" + id +
", name='" + name + '\'' +
", year=" + year +
", priceRent=" + priceRent +
", priceSell=" + priceSell +
", amount=" + amount +
'}';
}
}

M:N table does not update

I have m:n relationship between User and Document. I am creating Document object, getting List - setDocumentsForUsers() and then I am persisting that object. Problem is, that document is created in my database, but not M:N relationship. What am I doing wrong? I tried to call flush after persisting, but it did not help at all.
#Entity
public class User {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private long id;
#Column(name = "first_name")
private String firstName;
private String surname;
private String email;
private String password;
#ManyToMany
#JoinTable(
name = "users_roles",
joinColumns = #JoinColumn(
name = "user_id", referencedColumnName = "id"),
inverseJoinColumns = #JoinColumn(
name = "role_id", referencedColumnName = "id"))
private List<Role> roles;
#JsonIgnore
#ManyToMany
#JoinTable(
name="users_documents",
joinColumns = #JoinColumn(
name = "user_id", referencedColumnName = "id"),
inverseJoinColumns = #JoinColumn(
name="document_id", referencedColumnName = "id"))
private List<Document> usersDocuments;
#OneToMany(mappedBy="user")
private List<Document> sharedDocuments;
public User() {
}
public User(String firstName, String surname, String email, String password) {
this.firstName = firstName;
this.surname = surname;
this.email = email;
this.password = password;
}
public void setId(long id) {
this.id = id;
}
public long getId() {
return id;
}
public String getEmail() {
return email;
}
public void setEmail(String email){this.email = email;}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public void setRoles(List<Role> roles) {
this.roles = roles;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getSurname() {
return surname;
}
public void setSurname(String surname) {
this.surname = surname;
}
public List<Role> getRoles() {
return roles;
}
public List<Document> getUsersDocuments() {
return usersDocuments;
}
public void setUsersDocuments(List<Document> usersDocuments) {
this.usersDocuments = usersDocuments;
}
public List<Document> getSharedDocuments() {
return sharedDocuments;
}
public void setSharedDocuments(List<Document> sharedDocuments) {
this.sharedDocuments = sharedDocuments;
}
#Override
public boolean equals(Object o) {
if (this == o) return true;
if (!(o instanceof User)) return false;
User user = (User) o;
return getId() == user.getId();
}
#Override
public int hashCode() {
return Objects.hash(getId());
}
#Override
public String toString() {
return "User{" +
"firstName='" + firstName + '\'' +
", surname='" + surname + '\'' +
", email='" + email + '\'' +
", roles=" + roles +
'}';
}
}
My Document class:
#Entity
public class Document {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private long id;
#Column(unique = true)
private String name;
private String title;
private String description;
#Column(name = "resource_path")
private String resourcePath;
#Column(name = "upload_datetime", columnDefinition = "DATETIME")
#Temporal(TemporalType.TIMESTAMP)
private Date uploadDatetime;
#ManyToMany(mappedBy = "usersDocuments")
private List<User> documentsForUsers;
#ManyToOne
#JoinColumn(name="user_id", nullable=false)
private User user;
public Document() {
}
public Document(String title, String description){
this.title = title;
this.description = description;
}
public long getId() {
return id;
}
public void setId(long id) {
this.id = id;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
public String getResourcePath() {
return resourcePath;
}
public void setResourcePath(String resourcePath) {
this.resourcePath = resourcePath;
}
#Override
public String toString() {
return "Document{" +
"id=" + id +
", title='" + title + '\'' +
", description='" + description + '\'' +
", resourcePath='" + resourcePath + '\'' +
", uploadDatetime=" + uploadDatetime + '\'' +
". user=" + user;
}
#Override
public boolean equals(Object o) {
if (this == o) return true;
if (!(o instanceof Document)) return false;
Document document = (Document) o;
return getId() == document.getId();
}
#Override
public int hashCode() {
return Objects.hash(getId());
}
public Date getUploadDatetime() {
return uploadDatetime;
}
public void setUploadDatetime(Date uploadDatetime) {
// Date startDate = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss").parse(uploadDatetime.toString());
this.uploadDatetime = uploadDatetime;
}
public User getUser() {
return user;
}
public void setUser(User user) {
this.user = user;
}
public List<User> getDocumentsForUsers() {
return documentsForUsers;
}
public void setDocumentsForUsers(List<User> documentsForUsers) {
this.documentsForUsers = documentsForUsers;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
Perform this:
Optional<User> user = userService.getUserByEmail(createdBy);
Document document = new Document(title, desc);
document.setUploadDatetime(new Date());
document.setUser(user.get());
List<User> users = userService.getUsersByRoles(roles);
document.setDocumentsForUsers(users);
saveDocument(document);
#Override
public void saveDocument(Document document) {
entityManager.persist(document);
}

I think you need add the option to your #ManyToMany annotation: CascadeType.PERSIST.
By default, hibernate doesn't persists your relationship objects.
Try to use:
#ManyToMany(cascade = CascadeType.PERSIST)

Your class User is an Owner of relation #ManyToMany on
List<Document> usersDocuments;
as User has #JoinTable. Document class is an Inverse end.
If a Document is persisted then a data will be saved without relations. Because Inverse end cares only about itself but no relations.
By default you can persist a relation only from the owner side.
To be able to persist a relation from the inverse end then in your case as I tested:
In Document add cascade:
#ManyToMany(cascade = CascadeType.PERSIST, mappedBy = "usersDocuments")
private List<User> documentsForUsers;
and add a new code in your setter:
public void setDocumentsForUsers(List<User> documentsForUsers) {
if (documentsForUsers != null){
documentsForUsers.forEach(u -> {
u.getUsersDocuments().add(this); //here you should have not-null list u.getUsersDocuments()
});
}
this.documentsForUsers = documentsForUsers;
}
In User class add cascade:
#ManyToMany(cascade = CascadeType.PERSIST)
and
private List<Document> usersDocuments = new ArrayList<>();

How to update one field in my Entity using JPA Repository

I have Entity with 3 fields: id, lastname and phoneNumber. I want to create method which works for update all fields or only one or two.
I use Hibernate and JPA Repository.
When I try to update all fields everything works well but when for example i want to update only lastname without changing of phoneNumber I have in output null insted of old phoneNumber.
Here is my method from Controller:
#PutMapping("/students/update/{id}")
public String updateStudentById(#ModelAttribute Student student, #ModelAttribute StudentDetails studentDetails,
String lastname, String phoneNumber,
#PathVariable Long id) {
Optional<Student> resultOptional = studentRepository.findById(id);
//Student result =resultOptional.get();
resultOptional.ifPresent((Student result) -> {
result.getStudentDetails().setPhoneNumber(studentDetails.getPhoneNumber()); result.getStudentDetails().setLastname(studentDetails.getLastname());
studentRepository.save(result);
});
return "Student updated";
}
The class for update:
#DynamicUpdate
#Entity
public class StudentDetails {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#Column(name="lastname")
private String lastname;
#Column(name="phone_number")
private String phoneNumber;
public StudentDetails() {
}
public StudentDetails(Long id, String lastname, String phoneNumber) {
this.id = id;
this.lastname = lastname;
this.phoneNumber = phoneNumber;
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getLastname() {
return lastname;
}
public void setLastname(String lastname) {
this.lastname = lastname;
}
public String getPhoneNumber() {
return phoneNumber;
}
public void setPhoneNumber(String phoneNumber) {
this.phoneNumber = phoneNumber;
}
}
The class which has relation with StudentDetails:
#Entity
#Table(name = "student")
#DynamicUpdate
public class Student {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#Column(name = "name")
private String name;
#Column(name = "email")
private String email;
//#OneToMany(mappedBy = "student")
#ManyToMany
#JoinTable(name="course_student",joinColumns = #JoinColumn(name="student_id"),
inverseJoinColumns = #JoinColumn(name="course_id"))
private List<Courses> courses;
#OneToOne(cascade = CascadeType.ALL)
// #JoinColumn(name="studen/_details_id") // with this we have dobule student_details column
private StudentDetails studentDetails;
public List<Courses> getCourses() {
return courses;
}
public void setCourses(List<Courses> courses) {
this.courses = courses;
}
public StudentDetails getStudentDetails() {
return studentDetails;
}
public void setStudentDetails(StudentDetails studentDetails) {
this.studentDetails = studentDetails;
}
// Methods for StudentViewController
public String getLastname(){
return studentDetails.getLastname();
}
public String getPhoneNumber(){
return studentDetails.getPhoneNumber();
}
public Student() {
}
public Student(String name, String email, StudentDetails studentDetails) {
// this.id = id;
this.name = name;
this.email = email;
this.studentDetails = studentDetails;
}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
#Override
public String toString() {
return "Student{" +
"id=" + id +
", name='" + name + '\'' +
", email='" + email + '\'' +
'}';
}
}
I was looking for solution and I added #DynamicUpdate but still it doesn't work.

Your code works properly. When you only provide lastName parameter in your request, then the phoneNumber parameter will be mapped to null so you override the phoneNumer property in your entity with this null value.
Change the code in the following way:
resultOptional.ifPresent((Student result) -> {
if(studentDetails.getPhoneNumber()!=null) {
result.getStudentDetails().setPhoneNumber(studentDetails.getPhoneNumber());
}
if(studentDetails.getLastname()!=null) {
result.getStudentDetails().setLastname(studentDetails.getLastname());
}
studentRepository.save(result);
});
Unfortunately it raises an other problem: How will you delete these fields? (How can you set them explicitly to null? )
A possible solution if you check for the "" (empty string) and set the property to null if the parameter is empty string.
It will be a quite messy code anyway...
You should consider using the Spring Data Rest package. It automatically creates all of the standard REST endpoints for your entities and handles all of these PUT/PATCH/POST/DELETE issues out of the box.

why don't you just set the params of your request in you setters?
resultOptional.ifPresent((Student result) -> {
result.getStudentDetails().setPhoneNumber(phoneNumber);
result.getStudentDetails().setLastname(lastname);
studentRepository.save(result);
});

You forget set #OneToOne mapping in StudentDetails - StudentDetails also need field of type Student which will be annotated #OneToOne.
Also you have to ensure, that all of entity fields will be filled - read more about fetch types.

Hibernate one to one mapping with composed key doesn't work

I have one-to-one hibernate mapping between class Report and class Flyleaf.
The listed code is successfully executed and the mapping works good.
In my real model the primary key of a report is composed of an "id" and an "index" and so does flyleaf (because its primary key is the primary key of a report).
How can I change my code in order to make the primary key composite (I tried, but an exception was thrown when I want to get list of reports and I also tried to define the key as a PKClass).
(I'm using Hibernate and Spring if this can help)
#Entity
#Table(name="report_t")
public class Report {
private int id, nbPage;
private Flyleaf flyleaf;
public Report() {}
public Report(int id) {
this.id = id;
}
#Id
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
#Column(name="nb_page")
public int getNbPage() {
return nbPage;
}
public void setNbPage(int nbPage) {
this.nbPage = nbPage;
}
#OneToOne (fetch = FetchType.LAZY, mappedBy = "report", cascade = CascadeType.ALL)
public Flyleaf getFlyleaf() {
return flyleaf;
}
public void setFlyleaf(Flyleaf flyleaf) {
this.flyleaf = flyleaf;
}
#Override
public String toString() {
return "ID : "+id+"\t nb page : "+nbPage+"\n\t"+flyleaf;
}
}
#Entity
#Table(name="flyleaf_t")
public class Flyleaf {
private int id;
private String title, author, checker;
private Report report;
public Flyleaf() {}
public Flyleaf(int id) {
this.id = id;
}
#GenericGenerator(name = "generator", strategy = "foreign",
parameters = #Parameter(name = "property", value = "report_t"))
#Id
#GeneratedValue(generator = "generator")
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
#Column (name="title")
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
#Column (name="author")
public String getAuthor() {
return author;
}
public void setAuthor(String author) {
this.author = author;
}
#Column (name="checker")
public String getChecker() {
return checker;
}
public void setChecker(String checker) {
this.checker = checker;
}
#OneToOne(fetch = FetchType.LAZY)
#PrimaryKeyJoinColumn
public Report getReport() {
return report;
}
public void setReport(Report report) {
this.report = report;
}
#Override
public String toString() {
return "Flyleaf [id=" + id + ", title=" + title + ", author="
+ author + ", checker=" + checker + "]";
}
}

issue with Criteria when making an association on 2 tables with a fereign key

I m trying to learn about hibernate and Criteria.
i have 2 tables RATS and SICKNESS.
I set a foreign key in RATS : RATS.Sickness_Id = SICKNESS.ID.
I m trying to get with Criteria an equivalent of SQL:
select * from RATS r, SICKNESS s where s.id = r.sickness_id
I assumed it was this association:
session
.createCriteria(Rats.class)
.createCriteria(Sickness.class)
.toList()
This unfortunately ends up with:
org.hibernate.QueryException: could not resolve property: entities of: entities.Rats
Strange part is that both:
session.createCriteria(Rats.class).toList()
and
session.createCriteria(Sickness.class).toList()
work fine....
I'm a bit puzzled.
Here are my entities classes code:
#Entity
#Table(name = "RATS")
public class Rats implements java.io.Serializable {
private int id;
private Sickness sickness;
private String name;
private int age;
public Rats() {
}
public Rats(int id, String name, int age) {
this.id = id;
this.name = name;
this.age = age;
}
public Rats(int id, Sickness sickness, String name, int age) {
this.id = id;
this.sickness = sickness;
this.name = name;
this.age = age;
}
#Id
#Column(name = "ID", unique = true, nullable = false)
public int getId() {
return this.id;
}
public void setId(int id) {
this.id = id;
}
#ManyToOne(fetch = FetchType.LAZY)
#JoinColumn(name = "Sickness_Id")
public Sickness getSickness() {
return this.sickness;
}
public void setSickness(Sickness sickness) {
this.sickness = sickness;
}
#Column(name = "Name", nullable = false, length = 50)
public String getName() {
return this.name;
}
public void setName(String name) {
this.name = name;
}
#Column(name = "Age", nullable = false)
public int getAge() {
return this.age;
}
public void setAge(int age) {
this.age = age;
}
#Override
public String toString() {
String returnString = "My name is " + getName() + ", I am " + getAge()+ ". ";
returnString += getSickness() == null ? "I am healthy like hell! :)" : "I suffer from " + getSickness().getNom();
return returnString;
}
}
and
#Entity
#Table(name = "SICKNESS")
public class Sickness implements java.io.Serializable {
private int id;
private String nom;
private Set<Rats> ratses = new HashSet<Rats>(0);
public Sickness() {
}
public Sickness(int id) {
this.id = id;
}
public Sickness(int id, String nom, Set<Rats> ratses) {
this.id = id;
this.nom = nom;
this.ratses = ratses;
}
#Id
#Column(name = "Id", unique = true, nullable = false)
public int getId() {
return this.id;
}
public void setId(int id) {
this.id = id;
}
#Column(name = "Nom", length = 50)
public String getNom() {
return this.nom;
}
public void setNom(String nom) {
this.nom = nom;
}
#OneToMany(fetch = FetchType.LAZY, mappedBy = "sickness")
public Set<Rats> getRatses() {
return this.ratses;
}
public void setRatses(Set<Rats> ratses) {
this.ratses = ratses;
}
#Override
public String toString() {
return getNom()
+ ( getRatses() != null ? (", getRatses()=" + getRatses() + "]"): "" );
}
}
What did I miss?
Thanks in advance.

On Rats entity, the Sickness entity property is:
private Sickness sickness;
Accordingly, your association must use the same name.
session.createCriteria(Rats.class)
.createCriteria("sickness")
.list();
One other solution, should be to change Rats to use EAGER Fetch:
#ManyToOne(fetch = FetchType.EAGER)
#JoinColumn(name = "Sickness_Id")
public Sickness getSickness() {
return this.sickness;
}
public void setSickness(Sickness sickness) {
this.sickness = sickness;
}
and then use:
session.createCriteria(Rats.class)
.list();