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JPA created too many fields in table

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I am trying to map some entities to tables in MySQL database using Spring Boot JPA. I have a problem with one of the tables because in that one too many foreign keys are added. I highlighted the columns in the picture. I suppose that the problem might be linked with the fact that the Tutorial table has either One to Many or Many to Many relations with the other 3 tables, but I am not sure
#Entity(name = "authors")
public class Author {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "author_id")
private Long authorId;
#Column(name = "first_name", nullable = false, length = 100)
private String firstName;
#Column(name = "last_name", nullable = false, length = 100)
private String lastName;
#Column(name = "email", length = 320, unique = true)
private String email;
#Column(name = "job_title", length = 255)
private String jobTitle;
#Lob
#Type(type = "org.hibernate.type.BinaryType")
#Column(name = "profile_picture")
private byte[] profilePicture;
#Column(name = "about", length = 2000)
private String about;
#OneToMany(fetch = FetchType.LAZY)
#JoinColumn(name = "author_id")
private List<Tutorial> tutorials;
}
#Entity(name = "categories")
public class Category {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "category_id")
private Long categoryId;
#Column(name = "category_name", nullable = false, unique = true, length = 100)
private String categoryName;
#OneToMany(fetch = FetchType.LAZY)
#JoinColumn(name = "category_id")
private List<Tutorial> tutorials;
}
#Entity(name = "tutorials")
public class Tutorial {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "tutorial_id")
private Long tutorialId;
#Column(name = "tutorial_title", nullable = false, length = 150)
private String tutorialTitle;
#Column(name = "tutorial_description", nullable = false, length = 2000)
private String tutorialDescription;
#Column(name = "time_to_complete")
private Integer timeToComplete;
#Column(name = "date_published")
private Long datePublished;
#Column(name = "last_updated")
private Long lastUpdated;
#ManyToMany(fetch = FetchType.LAZY,
cascade = {
CascadeType.PERSIST,
CascadeType.MERGE
},
mappedBy = "tutorials")
private List<User> users = new ArrayList<>();
#ManyToOne(fetch = FetchType.EAGER)
private Category category;
#ManyToOne(fetch = FetchType.EAGER)
private Author author;
}
Tutorials is the table where the problems appear as 4 foreign keys are generate instead of two
#Entity(name = "users")
public class User {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "user_id")
private Long userId;
#Column(name = "first_name", nullable = false, length = 100)
private String firstName;
#Column(name = "last_name", nullable = false, length = 100)
private String lastName;
#Column(name = "user_name", nullable = false, unique = true, length = 100)
private String userName;
#Column(name = "age")
private Integer age;
#Column(name = "email", length = 320, unique = true)
private String email;
#ManyToMany(fetch = FetchType.LAZY,
cascade = {
CascadeType.PERSIST,
CascadeType.MERGE
})
#JoinTable(name = "users_tutorials",
joinColumns = { #JoinColumn(name = "user_id") },
inverseJoinColumns = { #JoinColumn(name = "tutorial_id") })
private List<Tutorial> tutorials = new ArrayList<>();
}

Try this changes:
remove #JoinColumn(name = "author_id")from Author and place in Tutorial:
#ManyToOne(fetch = FetchType.EAGER)
#JoinColumn(name = "author_id")
private Author author;
remove #JoinColumn(name = "category_id")from Category and place it in Tutorial as well:
#ManyToOne(fetch = FetchType.EAGER)
#JoinColumn(name = "category_id")
private Author author;
To get more information look here: Baeldung - Hibernate One to Many

multiple relationship between 2 table, how to design classes model that mapping with database by hibernate

I have 2 tables project and employee have multiple relationship. Project has many employees, employee can join many projects( many to many). project have one employee whose is team leader, an employee can manager many projects(many to one). So how do I design database, and classes model mapping with database. Some one help me
This is my code
class user
#Entity(name = "USERS")
public class Users {
#Id
#Column(name = "USER_ID", length = 6)
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Integer userId;
#Column(name = "USER_NAME", length = 50, nullable = false)
private String userName;
#Column(name = "PASS_WORD", length = 50, nullable = false)
private String passWord;
#Column(name = "FULL_NAME", length = 50, nullable = false)
private String fullName;
#Column(name = "EMAIL", length = 50, nullable = false)
private String email;
#Column(name = "PHONE", length = 11, nullable = true)
private String phone;
#Column(name = "STATUS", nullable = true)
private Boolean status;
#ManyToMany(fetch = FetchType.LAZY)
#JsonIgnore
#JoinTable(name = "USERPROJECT", joinColumns = { #JoinColumn(name =
"USER_ID") }, inverseJoinColumns = {
#JoinColumn(name = "PROJECT_ID") })
private List<Project> projects;
#OneToMany(mappedBy = "teamlead")
private List<Project> projectOfTeamLead;
//get set.....
}
class project
#Entity(name = "PROJECTS")
public class Project {
#Id
#Column(name = "PROJECT_ID", length = 6)
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Integer projectId;
#Column(name = "PROJECT_NAME", length = 50, nullable=false)
private String projectName;
#Column(name = "USER_CREATE_ID", length = 6, nullable=false)
private Integer userCreateId;
// #Column(name = "TEAM_LEAD_ID", length = 6, nullable=false)
// private Integer teamLeadId;
#Column(name = "TIME_START", nullable=true)
private Date timeStart;
#Column(name = "TIME_END", nullable=true)
private Date timeEnd;
#ManyToMany(mappedBy = "projects")
private List<Users> users;
#ManyToOne
#JoinColumn(name = "TEAM_LEAD_ID")
private Users teamlead;
//get set...
}

I think you need to make your database fit into 3nf (third normal form). You are describing a database that uses two tables, but I think you need three at least, that way you can describe what employees are on what project. A "team" table that uses the PK's from the other two tables should be used. Conventionally, you would name it something like "ProjectEmployees" as it is comprised of the PK's from the "Projects" table and the "Employees" table respectively. I hope that answers your question. If you don't understand what I'm talking about, I highly recommend you watch this.

How to fetch data from multiple table query by hibernate?

I have a user management application that allocate each user a team and one or many access to different application. Now for the reporting page I am trying to fetch data from two table (UserInfo & UserAppAccess) by Hibernate but I can't.
Here are the tables :
Table 1 (UserInfo):
#Entity
#Table(name = "user_info", uniqueConstraints = { #UniqueConstraint(columnNames = "username"), #UniqueConstraint(columnNames = "email") })
public class UserInfo implements java.io.Serializable {
public enum UserStatus {
active, inactive
}
public enum UserType {
user, creator
}
private static final long serialVersionUID = 2650114334774359089L;
#Id
#Column(name = "id", unique = true, nullable = false, length = 100)
private String id;
#Column(name = "username", unique = true, nullable = false, length = 50)
private String username;
#Column(name = "password", nullable = false, length = 80)
private String password;
#Column(name = "status", nullable = false, length = 10)
#Enumerated(EnumType.STRING)
private UserStatus status;
#Column(name = "type", nullable = false, length = 10)
#Enumerated(EnumType.STRING)
private UserType type;
#Column(name = "phone", nullable = true, length = 30)
private String phone;
#Column(name = "email", nullable = true, length = 50)
private String email;
#Column(name = "first_name", nullable = true, length = 50)
private String firstName;
#Column(name = "last_name", nullable = true, length = 50)
private String lastName;
#Column(name = "login", nullable = true, length = 100)
private long login;
#Column(name = "alert", nullable= true, length=500)
private String alert;
#OneToOne
#JoinColumn(name = "team_id")
private Team team;
}
Table 2 (Team):
#Entity
#Table(name = "team", uniqueConstraints = { #UniqueConstraint(columnNames = "team_name"), #UniqueConstraint(columnNames = "team_code") })
public class Team implements java.io.Serializable {
private static final long serialVersionUID = 7933770163144650730L;
#Id
#Column(name = "id", unique = true, nullable = false, length = 80)
private String id;
#Column(name = "team_name", unique = true, nullable = false, length = 100)
private String name;
#Column(name = "team_code", unique = true, nullable = false, length = 10)
private String code;
}
Table 3 (Access):
#Entity
#Table(name = "access_def")
public class Access implements java.io.Serializable {
private static final long serialVersionUID = 7933770163144650730L;
#Id
#Column(name = "id", unique = true, nullable = false, length = 80)
private String id;
#Column(name = "access_name", unique = true, nullable = false, length = 100)
private String name;
#Column(name = "access_code", unique = true, nullable = false, length = 10)
private String code;
}
Table 4 (Application):
#Entity
#Table(name = "application", uniqueConstraints = { #UniqueConstraint(columnNames = "name") })
public class Application implements java.io.Serializable {
private static final long serialVersionUID = 5803631085624275364L;
#Id
#Column(name = "name", nullable = false, length = 100)
private String name;
}
Table 5 (UserAppAccess):
#Entity
#Table(name = "user_app_access")
#Embeddable
public class UserAppAccess implements java.io.Serializable {
private static final long serialVersionUID = 7933770163144650730L;
#Id
#Column(name = "id", unique = true, nullable = false, length = 80)
private String id;
#OneToOne
#JoinColumn(name = "user_id")
private UserInfo userInfo;
#Column(name = "app_name", nullable = false, length = 100)
private String appName;
#OneToOne
#JoinColumn(name = "access_id")
private Access access;
}
I have a report page that allow Admin to select multiple options (for example: list all active users in Team test and application APP1).
here is my code to fetch the data but it is not working :
public List<?> getReport(String teamId,String appName,UserStatus active,UserStatus inactive) {
Session session = sessionFactory.getCurrentSession();
String hql = "SELECT u.firstName,u.username,u.status,u.lastName,u.phone,u.team From UserInfo u,AppAccess a WHERE u.status =? OR u.status =? AND u.team.id = ? AND a.appName = :appName ";
Query query = session.createQuery(hql);
query.setParameter(0, active);
query.setParameter(1, inactive);
query.setParameter(2, teamId);
query.setParameter("appName", appName);
System.out.println(query.list());
return query.list();
}
For instance when I pass
Active Users: Active
inactive User:null
team:test
application :app1
teamId :28f66133-26c3-442b-a071-4d19d64ec0aeappName :app1active :activeinactive:null
I am getting this back from my return query.list();
[[Ljava.lang.Object;#2961116f, [Ljava.lang.Object;#23bfa3a2, [Ljava.lang.Object;#7a8ff303, [Ljava.lang.Object;#9b88d2, [Ljava.lang.Object;#6333934d, [Ljava.lang.Object;#4f0bd71c, [Ljava.lang.Object;#125797cf, [Ljava.lang.Object;#34afa071, [Ljava.lang.Object;#764e75bc, [Ljava.lang.Object;#1913c652, [Ljava.lang.Object;#61413e5a, [Ljava.lang.Object;#264b898, [Ljava.lang.Object;#22930462, [Ljava.lang.Object;#6204cfa9, [Ljava.lang.Object;#29dd9285, [Ljava.lang.Object;#11be6f3c, [Ljava.lang.Object;#6d78d53d, [Ljava.lang.Object;#17f7cff1, [Ljava.lang.Object;#e74e382, [Ljava.lang.Object;#1c047338, [Ljava.lang.Object;#68286fe6, [Ljava.lang.Object;#36ca9a76, [Ljava.lang.Object;#2f62d514, [Ljava.lang.Object;#1932c5a, [Ljava.lang.Object;#6544c984, [Ljava.lang.Object;#70a2d0d, [Ljava.lang.Object;#2d13b417, [Ljava.lang.Object;#6894691f, [Ljava.lang.Object;#6781a7dc, [Ljava.lang.Object;#7133919a]

I'd suggest using native SQL and JDBC for reporting (see
How should I use Hibernate Mapping while dealing with huge data table)
For performance reasons it is desirable to create view model objects from result set right in the DAO. It may looks like mixing levels of abstraction (view layer with persistence layer), but it's ok when you need to fetch a big amounts of data and don't want to make unnecessary object transformations from persistence models to view models.
If you're want to stuck with hibernate, you may define a syntetic entity and map if on a view, containing only necessary columns from multiple:
#Entity
#Table("V_USER_REPORT")
public class UserAppData {
// columns from table "user"
#Id
#Column(name = "id", unique = true, nullable = false, length = 100)
private String id;
#Column(name = "username", unique = true, nullable = false, length = 50)
private String username;
// columns from table "user"
#Column(name = "app_name", nullable = false, length = 100)
private String appName;
// columns from table "team"
#Column(name = "team_id", unique = true, nullable = false, length = 80)
private String team_id;
#Column(name = "team_name", unique = true, nullable = false, length = 100)
private String name;
#Column(name = "team_code", unique = true, nullable = false, length = 10)
private String code;
// and so on...
}
Then you fetch such entity by parameters as you do it with normal entity.

By adding LEFT JOIN FETCH or FETCH ALL PROPERTIES. This will force JOINS insteed of lazy initialization
String hql = "SELECT u.firstName,u.username,u.status,u.lastName,u.phone,u.team From UserInfo u,AppAccess a FETCH ALL PROPERTIES WHERE u.status =? OR u.status =? AND u.team.id = ? AND a.appName = :appName ";
More information can be found in HQL Documentation

Firstly: I hope each of your entity classes have a toString() method (can be auto-generated with eclipse) so you can print them. Printing object reference isn't enough to infer whether/not you're getting what you want.
Secondly, the syntax of HQL joins is normally like this:
String queryString = "select distinct f from Foo f inner join foo.bars as b" +
" where f.creationDate >= ? and f.creationDate < ? and b.bar = ?";
(taken from How do you create a Distinct query in HQL)

Which data format is suitable to transfer data (result of left join db query) from servlet to JSP?

[using JPA, MySQL, MVC, Servlets, JSP]
If I read some data from database LEFT JOIN-ing three tables (inside method of DAO object) how should I format that result, so i can set it as request attribute (in servlet) and forwards to JSP page?
Entities(tables in db):
Post:
#Entity
#Table(name = "post")
public class Post implements Serializable {
#Id
#GeneratedValue(strategy = IDENTITY)
#Column(name = "post_id", unique = true, nullable = false)
private Integer id;
#Column(name = "post_title", length=300, unique = false, nullable = false)
private String title;
#Column(name = "post_date", unique = false, nullable = false)
private Date date;
#Column(name = "post_summary", length=1000, unique = false, nullable = true)
private String summary;
#Column(name = "post_content", length=50000, unique = false, nullable = false)
private String content;
#Column(name = "post_visitors", unique = false, nullable = false)
private Integer visitors;
#ManyToOne
#JoinColumn (name = "user_id", referencedColumnName="user_id", nullable = false)
private User user;
#ManyToOne
#JoinColumn (name = "category_id", referencedColumnName="category_id", nullable = false)
private Category category;
#OneToMany(cascade = { ALL }, fetch = LAZY, mappedBy = "post")
private Set<Comment> comments = new HashSet<Comment>();
...
Entity Comment:
#Entity
#Table(name = "comment")
public class Comment implements Serializable {
#Id
#GeneratedValue(strategy = IDENTITY)
#Column(name = "comment_id", unique = true, nullable = false)
private Integer id;
#Column(name = "comment_title", length=300, unique = false, nullable = false)
private String title;
#Column(name = "comment_date", unique = false, nullable = false)
private Date date;
#Column(name = "comment_content", length=600, unique = false, nullable = false)
private String content;
#ManyToOne
#JoinColumn (name = "user_id", referencedColumnName="user_id", nullable = false)
private User user;
#ManyToOne
#JoinColumn (name = "post_id", referencedColumnName="post_id", nullable = false)
private Post post;
...
Entity User:
#Entity
#Table(name = "user")
public class User implements Serializable {
#Id
#GeneratedValue(strategy = IDENTITY)
#Column(name = "user_id", unique = true, nullable = false)
private Integer id;
#Column(name = "user_name", length=45, unique = false, nullable = false)
private String name; // "first_name" + ' ' + "last_name"
//URL address to user's image
#Column(name = "user_image", length=500, unique = false, nullable = true)
private String image;
#Column(name = "user_username", length=45, unique = false, nullable = false)
private String username;
#Column(name = "user_password", length=45, unique = false, nullable = false)
private String password;
...
So, I would like to make a method, probably inside PostDAO object that will look something like this:
public <SomeDataTypeFormat???> getPostsSummaries(){
Query q = em.createNativeQuery("SELECT
post_title,
post_summary,
post_date,
COUNT(comment_id) AS comment_cnt,
user.user_name
FROM
post
LEFT JOIN user USING(user_id)
LEFT JOIN comment USING(post_id)
GROUP BY
post_id
ORDER BY
comment_cnt DESC");
...
}
Method returns some fields from all three tables in database.
Do I need to make separate class and store those data in objects of that class? Or JSON (although I haven't worked with it yet)?
What is the practice? What is easiest data format to use and forward from servlet to JSP, for some fields gotten as a result of joining couple tables?

It depends on your objective; to get the data to the browser, JSON and AJAX isn't a bad choice. To get the data to the JSP (from the Servlet), you'll probably want a Data Transfer Object (or possibly an immutable Value Object).

ORA-01400 cannot insert null error in one to one relationship

i have this code
public void guardarAspirante(AspiranteDTO aspiranteDTO) {
Aspirante aspirante = new Aspirante();
String usuarioMovimiento = AspiranteCN.class.getSimpleName();
Date fecha = new Date();
aspirante.setCodigoAlumno(aspiranteDTO.getCodigoUniversitario());
aspirante.setNombre(aspiranteDTO.getNombre());
aspirante.setApellidoPaterno(aspiranteDTO.getPrimerApellido());
aspirante.setApellidoMaterno(aspiranteDTO.getSegundoApellido());
aspirante.setUsuarioMovimiento(usuarioMovimiento);
aspirante.setFechaMovimiento(fecha);
Solicitud solicitud = new Solicitud(aspirante.getSolicitudId());
solicitud.setAspirante(aspirante);
solicitud.setSolicitudId(aspirante.getSolicitudId());
solicitud.setOfertaId(aspiranteDTO.getOfertaAcademica());
solicitud.setPeriodoId(aspiranteDTO.getPeriodo());
solicitud.setAportacion(aspiranteDTO.getAportacionVoluntaria());
solicitud.setFechaMovimiento(fecha);
solicitud.setUsuarioMovimiento(usuarioMovimiento);
aspirante.setSolicitud(solicitud);
....
aspiranteDAO.persist(aspirante);
}
and this error
Internal Exception: java.sql.SQLException: ORA-01400: cannot insert NULL into ("RPINGRE"."ARE_SOLI"."ARE_SOLI_SOLIASPI_ID")
This is Aspirante Entity (Fragment)
#Entity
#Table(name = "ARE_SOLIASPI", catalog = "", schema = "RPINGRE")
public class Aspirante implements Serializable {
private static final long serialVersionUID = 1L;
#SequenceGenerator(sequenceName = "RPINGRE.SQ_ARE_SOLIASPI",
name = "RPINGRE.SQ_ARE_SOLIASPI",
initialValue = 1,
allocationSize = 1)
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "RPINGRE.SQ_ARE_SOLIASPI")
#Id
#Basic(optional = false)
#Column(name = "ARE_SOLIASPI_ID")
private Long solicitudId;
#Basic(optional = false)
#Column(name = "ARE_SOLIASPI_CODIGO")
private String codigoAlumno;
#Basic(optional = false)
#Column(name = "ARE_SOLIASPI_NOMBRE")
private String nombre;
#Column(name = "ARE_SOLIASPI_APE_PATERNO")
private String apellidoPaterno;
#Column(name = "ARE_SOLIASPI_APE_MATERNO")
private String apellidoMaterno;
#Basic(optional = false)
#Column(name = "ARE_SOLIASPI_MOV_USUARIO")
private String usuarioMovimiento;
#Basic(optional = false)
#Column(name = "ARE_SOLIASPI_MOV_FECHA")
#Temporal(TemporalType.TIMESTAMP)
private Date fechaMovimiento;
#OneToOne(cascade = CascadeType.ALL, mappedBy = "aspirante", fetch = FetchType.LAZY)
private Solicitud solicitud;
and Solicitud Entity (Fragment)
#Entity
#Table(name = "ARE_SOLI", catalog = "", schema = "RPINGRE")
public class Solicitud implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#Basic(optional = false)
#Column(name = "ARE_SOLI_SOLIASPI_ID")
private Long solicitudId;
#Basic(optional = false)
#Column(name = "ARE_SOLI_MOV_USUARIO")
private String usuarioMovimiento;
#Basic(optional = false)
#Column(name = "ARE_SOLI_MOV_FECHA")
#Temporal(TemporalType.TIMESTAMP)
private Date fechaMovimiento;
#Column(name = "ARE_SOLI_PERIODO_ID")
private String periodoId;
#Column(name = "ARE_SOLI_OFERTA_ID")
private Long ofertaId;
#Column(name = "ARE_SOLI_APORTACION")
private Long aportacion;
#JoinColumn(name = "ARE_SOLI_SOLIASPI_ID", referencedColumnName = "ARE_SOLIASPI_ID", insertable = false, updatable = false, nullable = false)
#OneToOne(optional = false, fetch = FetchType.LAZY)
private Aspirante aspirante;
.....
}

try changing GenerationType.SEQUENCE to GenerationType.Auto.

The ORA-01400 error says that you are trying to insert a NULL into a column defined as NOT NULL.
I suggest you ether set a default value on the column or have your code make sure the NOT NULL columns have data before you do the INSERT (or use an NVL function in your INSERT statement)