It should be easy. Oracle has defined "generate always" for an id column. So there is no need to add this id to the insert statement. How do i define my entity that it is handling right.
#Entity
public class Example {
#Id
#GeneratedValue // if i remove this annotation than hibernate complains that i need to set it manually
#Column(name="ID", insertable=false, updatable=false)
private Long id;
}
in the error message i see that it still tries to add the id to the query.
My work-around for the column. Add the #id to an other column and remove the id column from entity definition :-D
I've a springboot app where I need to implement db partitioning (by "range") for posts table based on posted_at attribute value.
Entity:
#Entity
public class Post {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(updatable = false, nullable = false)
private BigInteger id;
private String title;
private Date postedDate;
.....
}
Liquibase migration:
<databaseChangeLog
xmlns="http://www.liquibase.org/xml/ns/dbchangelog"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://www.liquibase.org/xml/ns/dbchangelog http://www.liquibase.org/xml/ns/dbchangelog/dbchangelog-3.0.xsd">
<changeSet id="00001" author="author">
<sql splitStatements="true">
CREATE TABLE posts (
id bigint primary key,
title varchar(200),
posted_at timestamp with time zone) PARTITION BY RANGE (posted_at)
</sql>
</changeSet>
When I run the above db migration, Postgres complains that I should add primary key also into the partition keys which I don't really want to. If I remove the primary key from the table, JPA will start throwing exception saying that I cannot have an entity without #Id field. How can this be resolved?
PS: I'm using plain sql inside Liquibase migration as liquibase has no direct support for db partitioning.
My spring boot project uses an existing database, I have a new model entity/table in my project that must have a foreign key constraint with an existing table in the database.
I've tried to find solution online but all the answers are for the case where both the tables are present as entities in that project and using some #ManyToOne, #OneToMany annotations.
I can't define those annotations because I don't have the reference table as an entity or model in my project.
Let's say I have class like:
#Entity(name = "user")
public class User {
#Id
#GeneratedValue
private long userId;
private long departmentId;
I want to put a foreign key contraint on the departmentId column to reference to id column of the existing department table that isn't defined as a model or entity in my project.
Thanks
Just do it as normal
example
#Column(name = "department_id")
private Department departmentId;
You can later access it Department.departmentId. Hope this helps.
Try it like this
#ManyToOne
#JoinColumn(name="(column name of current entity)", referencedColumnName="(column name in target entity)")
private Department departmentId;
you can skip the referencedColumnName if the column name is same in both the entities
In my spring mvc app, i have the following object. I am trying to make a visual of data using devtool in my app.
#Entity
#Data
public class ConsultationRequest {
#Id
#GeneratedValue
private Long id;
private String name;
private String email;
private String purpose;
private String programme;
private int year;
private String language;
private String comments;
#Enumerated(EnumType.STRING)
private ConsultationStatus status;
}
Then i used the jpa to make the entity:
#Repository
public interface ConsultationRequestRepository extends JpaRepository<ConsultationRequest, Long> {
}
The problem is when i load my application, i face with 2 errors:
Unsuccessful: drop sequence hibernate_sequence
[36morg.hibernate.tool.hbm2ddl.SchemaExport Sequence "HIBERNATE_SEQUENCE" not found; SQL statement:
Then when i open the
http://localhost:8080/h2-console/
I cannot see the table.
It seems that the in the boot process, table is not made.
Update your code as below:
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
As you have not specified a sequence table name, hibernate will look for a sequence table named as hibernate_sequence and use it as default.
For Oracle/Postgres, increment fields used are sequence tables.
In MySql, there are increment fields that automatically increment.
If someone is getting this error with Spring Boot testing(with H2) , we have to use following in the application.properties(or whatever profile we are using) :
spring.jpa.hibernate.ddl-auto=create-drop
Setting the following property in the properties file helped me solve the hibernate_sequence problem for hibernate 5.4v
spring:
jpa:
hibernate:
use-new-id-generator-mappings: false
Check persistence.xml
property name="hibernate.hbm2ddl.auto" value="create"
not hdm2ddl
This worked in my case.
SQL operation ERROR when start app spring-boot.
I added the setting in spring properties and solved: in the spring:jpa.hibernate.ddl-auto= create-drop to hibernate be able create or drop table automatically.
If you use a 2nd cache with liquidbase, you have to add the sequence in the changelog like this:
<changeSet author="liquibase-docs"
id="createSequence-example">
<createSequence catalogName="cat" cycle="false"
incrementBy="1" ordered="true" schemaName="public"
sequenceName="hibernate_sequence" startValue="0" />
</changeSet>
For spring-boot 2.7.x and h2 2.x you need to add MODE=LEGACY; in the database connection:
example application.yml:
spring:
datasource:
url: jdbc:h2:mem:test;MODE=LEGACY;
exemple application.properties:
spring.datasource.url=jdbc:h2:mem:test;MODE=LEGACY;
For Mysql:
the auto-increment is not added, modify ur table:
ALTER TABLE table_name MODIFY COLUMN id BIGINT AUTO_INCREMENT=1
I built an entity with id using oracle sequence like that.
#Entity
#Table(name="C_ESTIMATE")
public class Estimate implements Serializable{
private static final long serialVersionUID = 1L;
public Estimate(){}
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "estimatenoGen")
#SequenceGenerator(name="estimatenoGen",sequenceName="AUTOSERIALNO",allocationSize=1)
#Column(name="ESTIMATENO")
private long id;
}
When I call em.persist(new Estimate()),
EclipseLink prompts Internal Exception: java.sql.SQLIntegrityConstraintViolationException: ORA-00001: unique constraints . Sometimes it works correctly, sometimes failure, it is so strange.
This entity was deployed several weblogic servers.
Has EclipseLink bug on generating id using oracle sequence?
There should not be any issue on Oracle.
Can recreate the issue? Enable logging, is a duplicate id being used?
How did you create your SEQUENCE object on the database?