Pfthb

I have SpringBoot project with Spring Data. Extra column being created when I use the same column name for 2 tables mapped using ManyToOne Relation. I have Address table with column name 'id' and AddressType table with column 'id'. When I start the Spring Boot application with this, I see an extra column (address_id) created on Address table.

Address.java

package com.springtesting.model;

import lombok.Data;

import javax.persistence.*;

@Entity
@Data
@Table(name = "address")
public class Address


 @Id
 @GeneratedValue(strategy = GenerationType.AUTO)
 @Column(name = "id")
 private Long id;

 @Column(name = "street_name")
 private String streetName;

 @Column(name = "apartment")
 private String apartment;

 @Column(name = "city")
 private String city;

 @Column(name = "state")
 private String state;

 @Column(name = "country")
 private String country;

 @Column(name = "zip_code")
 private String zipCode;

 @ManyToOne(cascade = CascadeType.ALL)
 @JoinColumn(name = "address_type_id")
 private AddressType addressType;

 public Address()
 
 

 public Address(String streetName, String apartment, String city, String state, String country, String zipCode, AddressType addressType)
 
 this.streetName = streetName;
 this.apartment = apartment;
 this.city = city;
 this.state = state;
 this.country = country;
 this.zipCode = zipCode;
 this.addressType = addressType;
 

and

AddressType.java

package com.springtesting.model;

import lombok.Data;
import lombok.NonNull;

import javax.persistence.*;

@Entity
@Data
@Table(name = "address_type")
public class AddressType

 @Id
 @GeneratedValue(strategy = GenerationType.AUTO)
 @Column(name = "id")
 private Long id;

 @Column(name = "type")
 @NonNull
 private String type;

 public AddressType()
 

 

 public AddressType(String type)
 
 

when I start the Spring Boot application, I see extra column (address_id)

Table Structure on Mysql

I'm not sure this will fix your issue, but try changing the @GeneratedValue(strategy = GenerationType.AUTO) to @GeneratedValue(strategy = GenerationType.IDENTITY), or give it a "native" GenericGenerator, as discussed here. Apparently GenerationType.AUTO does not play nice with MySQL from Hibernate 5+.

A couple of other notes:

• You probably don't want to use Lombok's @NonNull, instead just use @Column(name = "type", nullable = false). In fact if the POJO is created through the default constructor, Lombok's @NonNull wouldn't do anything anyway since it's annotated over a field.




• You don't need the cascade = CascadeType.ALL above the AddressType since you probably don't want to accidentally update/delete/or create new AddressTypes through the Address entity. Just annotating it @ManyToOne should be enough.