问题
I'm having some issues storing entries into my database. I am using the following heirarchy:
I have a parent class PageContent and two subclasses TextEntry and Image however when I try to store more than PageContent entity I get the following exception:
HTTP Status 500 - Request processing failed; nested exception is org.springframework.dao.DataIntegrityViolationException: Duplicate entry '2' for key 'groups_groupId'; SQL [n/a]; constraint [null]; nested exception is org.hibernate.exception.ConstraintViolationException: Duplicate entry '2' for key 'groups_groupId'
Here are the relevant classes
Group.java:
package com.youthministry.domain;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
@Entity(name="GROUP_DETAILS")
public class Group {
@Id
@GeneratedValue(strategy=GenerationType.AUTO)
private Long groupId;
@Column(name = "GROUP_NAME", unique = true, nullable = false)
private String groupName;
private String groupDesc;
/*public String getIdAsString() {
return new Long(groupId).toString();
}*/
public Long getGroupId() {
return groupId;
}
public void setGroupId(Long groupId) {
this.groupId = groupId;
}
public String getGroupName() {
return groupName;
}
public void setGroupName(String groupName) {
this.groupName = groupName;
}
public String getGroupDesc() {
return groupDesc;
}
public void setGroupDesc(String groupDesc) {
this.groupDesc = groupDesc;
}
}
PageContent.java
package com.youthministry.domain;
import java.util.ArrayList;
import java.util.Collection;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Inheritance;
import javax.persistence.InheritanceType;
import javax.persistence.OneToMany;
@Entity
@Inheritance (strategy=InheritanceType.JOINED)
public class PageContent {
@Id
@GeneratedValue(strategy=GenerationType.AUTO)
private Long pageContentId;
@Column(name="PAGE_CONTENT_NAME", nullable=false)
private String pageContentName;
@Column(name="LOCATION", nullable=false)
private String location;
@OneToMany(cascade=CascadeType.REMOVE)
private Collection<Group> groups = new ArrayList<Group>();
public Long getPageContentId() {
return pageContentId;
}
public void setPageContentId(Long pageContentId) {
this.pageContentId = pageContentId;
}
public String getPageContentName() {
return pageContentName;
}
public void setPageContentName(String pageContentName) {
this.pageContentName = pageContentName;
}
public String getLocation() {
return location;
}
public void setLocation(String location) {
this.location = location;
}
public Collection<Group> getGroups() {
return groups;
}
public void setGroups(Collection<Group> groups) {
this.groups = groups;
}
}
Image.java
package com.youthministry.domain;
import javax.persistence.Entity;
@Entity
public class Image extends PageContent {
private String pathToImage;
private String altText;
private String titleText;
public String getPathToImage() {
return pathToImage;
}
public void setPathToImage(String pathToImage) {
this.pathToImage = pathToImage;
}
public String getAltText() {
return altText;
}
public void setAltText(String altText) {
this.altText = altText;
}
public String getTitleText() {
return titleText;
}
public void setTitleText(String titleText) {
this.titleText = titleText;
}
}
TextEntry.java
package com.youthministry.domain;
import javax.persistence.Entity;
import javax.persistence.Lob;
@Entity
public class TextEntry extends PageContent {
private String contentTitle;
@Lob
private String contentBody;
public String getContentTitle() {
return contentTitle;
}
public void setContentTitle(String contentTitle) {
this.contentTitle = contentTitle;
}
public String getContentBody() {
return contentBody;
}
public void setContentBody(String contentBody) {
this.contentBody = contentBody;
}
}
I have tried to resolve this and my hunch is that it has to do with the CascadeType that I'm using and I had thought that changing it to Cascade on delete instead which did remove the duplicative insert for the Group Entity however I still receive the aforementioned exception.
Here is the link to the git repo: http://github.com/dmcquillan314/YouthMinistryHibernate
Any help is appreciated thanks in advance.
Here are the create table scripts for all relevant db tables:
CREATE TABLE `PageContent_GROUP_DETAILS` (
`PageContent_pageContentId` bigint(20) NOT NULL,
`groups_groupId` bigint(20) NOT NULL,
UNIQUE KEY `groups_groupId` (`groups_groupId`),
KEY `FK43215F8D912C9AF9` (`PageContent_pageContentId`),
KEY `FK43215F8D11E7050D` (`groups_groupId`),
CONSTRAINT `FK43215F8D11E7050D` FOREIGN KEY (`groups_groupId`) REFERENCES `GROUP_DETAILS` (`groupId`),
CONSTRAINT `FK43215F8D912C9AF9` FOREIGN KEY (`PageContent_pageContentId`) REFERENCES `PageContent` (`pageContentId`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1
CREATE TABLE `Image` (
`altText` varchar(255) DEFAULT NULL,
`pathToImage` varchar(255) DEFAULT NULL,
`titleText` varchar(255) DEFAULT NULL,
`pageContentId` bigint(20) NOT NULL,
PRIMARY KEY (`pageContentId`),
KEY `FK437B93B4AAD3F6E` (`pageContentId`),
CONSTRAINT `FK437B93B4AAD3F6E` FOREIGN KEY (`pageContentId`) REFERENCES `PageContent` (`pageContentId`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1
CREATE TABLE `PageContent` (
`pageContentId` bigint(20) NOT NULL AUTO_INCREMENT,
`LOCATION` varchar(255) NOT NULL,
`PAGE_CONTENT_NAME` varchar(255) NOT NULL,
PRIMARY KEY (`pageContentId`)
) ENGINE=InnoDB AUTO_INCREMENT=5 DEFAULT CHARSET=latin1
CREATE TABLE `GROUP_DETAILS` (
`groupId` bigint(20) NOT NULL AUTO_INCREMENT,
`groupDesc` varchar(255) DEFAULT NULL,
`GROUP_NAME` varchar(255) NOT NULL,
PRIMARY KEY (`groupId`)
) ENGINE=InnoDB AUTO_INCREMENT=3 DEFAULT CHARSET=latin1
回答1:
You are making groups_groupId
unique.
But the relationship in the PageContent
class is OneToMany
.
In the relationship table will be like below.
PageContentID GroupID
1 2
1 1
1 3
2 1
2 3
So making any column unique in this relationship table is a no no.
What I meant was for you to remove
UNIQUE KEY `groups_groupId` (`groups_groupId`),
from
CREATE TABLE `PageContent_GROUP_DETAILS` (
`PageContent_pageContentId` bigint(20) NOT NULL,
`groups_groupId` bigint(20) NOT NULL,
UNIQUE KEY `groups_groupId` (`groups_groupId`),
KEY `FK43215F8D912C9AF9` (`PageContent_pageContentId`),
KEY `FK43215F8D11E7050D` (`groups_groupId`),
CONSTRAINT `FK43215F8D11E7050D` FOREIGN KEY (`groups_groupId`) REFERENCES `GROUP_DETAILS` (`groupId`),
CONSTRAINT `FK43215F8D912C9AF9` FOREIGN KEY (`PageContent_pageContentId`)
REFERENCES `PageContent` (`pageContentId`))
ENGINE=InnoDB DEFAULT CHARSET=latin1
来源:https://stackoverflow.com/questions/15801701/duplicate-entry-exception-hibernate