I want to integrate a JDBC based application into an Java EE application running in GlassFish which uses EclipseLink JPA 2.5 with MariaDB (a MySQL clone).
The JDBC based application imports data from flat files into some database tables and requires to update the next serial value for the primary keys by executing:
UPDATE dbtable SET nextid = 4711 WHERE name = 'table4Import';
using a standard JDBC connection. This statement throws an SQL timeout exception because the row is locked. It seems to be locked by EclipseLink which uses the same table for its table generator. Here is (parts of) the table containing the serial values:
CREATE TABLE dbtable (
dbtid bigint not null primary key,
dbtname varchar ( 50 ) not null,
dbtnextid bigint );
This is the code for one of the JPA entities:
#Entity
#Access(AccessType.PROPERTY)
#Table( name = "table4Import" )
public class Table4ImportClass {
private Long id = null;
#NotNull
#Id
#TableGenerator( name="table4Import", allocationSize=1,
table="dbtable", pkColumnName="dbtname",
pkColumnValue="table4Import", valueColumnName="nextid" )
#GeneratedValue( generator="table4Import", strategy=GenerationType.TABLE )
public Long getId() { return this.id; }
...
Addendum: It is not even possible to insert a new row into that table. EclipseLink seems to lock the complete table. It is still possible to modify the table (insert & update) from another program. The lock scope seems to be the JVM in which EclipseLink is running.
Addendum 2: Put this as a bug into EclipseLink bug tracker 455756
Related
I tried to use Spring Data R2dbc/Postgres in a sample application.
Spring Boot 2.4.0-M2
R2dbc Postgres (managed by Spring Boot)
Spring Data R2dbc 1.2.0-M2(managed by Spring Boot)
The table scripts.
CREATE SEQUENCE IF NOT EXISTS ORDERS_ID_SEQ;
CREATE TABLE IF NOT EXISTS ORDERS(
ID INTEGER NOT NULL PRIMARY KEY DEFAULT nextval('ORDERS_ID_SEQ') ,
CUST_ID BIGINT NOT NULL,
AMOUNT REAL NOT NULL
);
ALTER SEQUENCE ORDERS_ID_SEQ OWNED BY ORDERS.ID;
The data.sql:
-- INSERT SAMPLE DATA
DELETE FROM ORDERS;
INSERT INTO ORDERS(CUST_ID, AMOUNT) VALUES (1, 100.2);
I use a ResourceDatabasePopulator to populate the data, it works.
But when I was trying to save the data by Repository, failed.
#Table(value = "ORDERS")
#Data
#Builder
#NoArgsConstructor
#AllArgsConstructor
public class Order implements Serializable {
#Id
#Column(value = "ID")
private Integer id;
#Column(value = "CUST_ID")
private Long customerId;
// use BigDecimal or Java Money API in the real-world application.
#Column(value = "AMOUNT")
private Double amount;
}
public interface OrderRepository extends R2dbcRepository<Order,Integer> {
}
// in application runner.
orders .save(Order.builder().customerId(c.getId()).amount(201.0).build())
It threw an exception like this:
reactor.core.Exceptions$ErrorCallbackNotImplemented: java.lang.UnsupportedOperationException: Binding parameters is not supported for the statement 'INSERT INTO ORDERS (CUST_ID, AMOUNT) VALUES (?, ?)'
Caused by: java.lang.UnsupportedOperationException: Binding parameters is not supported for the statement 'INSERT INTO ORDERS (CUST_ID, AMOUNT) VALUES (?, ?)'
at io.r2dbc.postgresql.SimpleQueryPostgresqlStatement.bind(SimpleQueryPostgresqlStatement.java:78) ~[r2dbc-postgresql-0.8.4.RELEASE.jar:0.8.4.RELEASE]
at io.r2dbc.postgresql.SimpleQueryPostgresqlStatement.bind(SimpleQueryPostgresqlStatement.java:44) ~[r2dbc-postgresql-0.8.4.RELEASE.jar:0.8.4.RELEASE]
The complete codes is here.
Updated: Give up extending from AbstractR2dbcConfiguration, and get resovled when following the official guide.
I have a basic spring application, with a simple entity. I have a flyway script, to create the postgres table, and add some starting data.
create table user (
id serial primary key,
username varchar (50) unique not null,
password varchar (150) not null
);
insert into user (id, username, password) values (1, 'name', 'somehashed');
insert into etc...
I've set up my entity as follows:
#Entity
#Table(name = "user")
public class User {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "id", updatable = false, columnDefinition = "serial")
private Long id;
...
other fields, constructor, getters setters etc...
My problem is, that on start-up, the basic entities are persisted by flyway, but upon trying to save a new entity, hibernate tries to give it the ID 1, although it is already given to another one.
I tried it also with SEQUENCE strategy, the problem didn't get solved.
Ok, problem was that I specified explicitly the ID I wanted to give while the insert script, and I didn't let postgres do the magic...
I have an entity
#Entity
public class Book {
#Id
#Column(name = "book_id")
#SequenceGenerator(name = "book_book_id_seq", sequenceName = "book_book_id_seq", allocationSize = 1)
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "book_book_id_seq")
private Long id;
// getter, setter & other fields
}
with schema
CREATE TABLE book
(
book_id bigint NOT NULL DEFAULT nextval('book_book_id_seq'::regclass),
CONSTRAINT book_pkey PRIMARY KEY (book_id)
)
What I want to achieve is sometime I would like to use sequence/id generated by database, but sometime the data is created at other place and I would like to create with existing (manual) id.
I can't set the id manually with Spring Data JPA way (using CrudRepository) or JPA way (using EntityManager), but no issue with native query. Is this JPA limitation? Any workaround for my issue?
Book book01 = new Book();
bookRepo.save(book01); // Book with id 1 is created
Book book02 = new Book();
book02.setId(5555L);
bookRepo.save(book02); // Does not create book with id 5555, but 2
Query nativeQuery = entityManager.createNativeQuery("INSERT INTO book VALUES (6666);");
nativeQuery.executeUpdate(); // Book with id 6666 is created
Query nativeQuery02 = entityManager.createNativeQuery("INSERT INTO book DEFAULT VALUES;");
nativeQuery02.executeUpdate(); // Book with id 3 is created
I am using PostgreSQL 9.4, Hibernate 5 and Java 8.
On persist, if a field is annotated with #GeneratedValue, it will generate the ID with whatever strategy is specified. Then it will set value of the id field with the generated value. So if the id is manually set using setId() before persisting, this will just be overriden.
If you want, you can use em.persist for auto-generated IDs. Then use native SQL for manually setting the Id, since native SQLs will bypass whatever mapping you have on your entity.
Yes, by default Hibernate org.hibernate.id.SequenceGenerator always generate new id. What you should do is to override public Serializable generate(SessionImplementor session, Object obj) method, where if your obj (cast to your entity first) has id, then return the id, else get it from database sequence.
I'm trying to use entities with a MySQL ndbcluster table. This table type doesn't allow foreign keys, but up until now it hasn't been a problem with my entities.
However, I have run into a bit of a problem, when I try to load an entity using the EntityManager's createNativeQuery method. I need to use this method due to my inability to do this: How to make a CriteriaBuilder join with a custom "on" condition?
My MySQL table looks like this:
CREATE TABLE `category` (
`id` SMALLINT(6) NOT NULL AUTO_INCREMENT,
`category_id` SMALLINT(6) NULL DEFAULT NULL,
PRIMARY KEY (`id`),
INDEX `category_id` (`category_id`)
)
COLLATE='utf8_general_ci'
ENGINE=ndbcluster
ROW_FORMAT=DEFAULT
If I change the table engine to innodb, and add foreign keys, the createNativeQuery method works fine.
My entity class looks like this:
#Entity
#Table(name = "category")
public class Category implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Basic(optional = false)
#Column(name = "id")
private Short id;
#OneToMany(mappedBy = "categoryId")
private List<Category> categoryList;
#JoinColumn(name = "category_id", referencedColumnName = "id")
#ManyToOne
private Category categoryId;
public Category() {
}
// getters and setters
}
Even without foreign keys, this entity works fine when I use the CriteriaBuilder for a query, but unfortunately not everything is possible with the CriteriaBuilder.
I get an error when I call getResultList on a Query object created with createNativeQuery. I don't know if this is a bug, or if something should be added to my entity class to make this work.
The error says:
Exception [EclipseLink-6044] (Eclipse Persistence Services - 2.3.2.v20111125-r10461): org.eclipse.persistence.exceptions.QueryException
Exception Description: The primary key read from the row [ArrayRecord(
=> 2519
=> 2463
=> Tools)] during the execution of the query was detected to be null. Primary keys must not contain null.
Query: ReadAllQuery(referenceClass=Category sql="select * from `category`")
at org.eclipse.persistence.exceptions.QueryException.nullPrimaryKeyInBuildingObject(QueryException.java:895)
at org.eclipse.persistence.internal.descriptors.ObjectBuilder.buildObject(ObjectBuilder.java:584)
at org.eclipse.persistence.internal.descriptors.ObjectBuilder.buildObject(ObjectBuilder.java:560)
at org.eclipse.persistence.queries.ObjectLevelReadQuery.buildObject(ObjectLevelReadQuery.java:717)
at org.eclipse.persistence.queries.ReadAllQuery.registerResultInUnitOfWork(ReadAllQuery.java:769)
...
My table contains 1 row, where id=1 and category_id=null, so there are no primary keys with a null-value, despite what the error says. If I remove that row or set category_id=1, I don't get an error.
Need help, please.
Managed to make it work by switching from EclipseLink (JPA 2.0) to OpenJPA (JPA 2.0). Seems like there is a bug somewhere in EclipseLink 2.3.2 and/or GlassFish 3.1.2.2.
I've used EclipseLink (JPA 2.0) in another project of mine, using a slightly different version Netbeans + GlassFish 3.1.1, where I used createNativeQuery on an entity class for a non-relational myisam table. This never caused any problem. It really must be a bug.
But problem solved. Bye, bye EclipseLink, hello OpenJPA.
The issue is case sensitivity. In MySQL your column "id" will be defined in the database as "ID" unless you quote it. If you switch your mappings to upper case it should fix the issue (i.e. "ID").
You could also quote the column name ("'id'")
or set the persistence unit property,
"eclipselink.jpa.uppercase-column-names"="true"
I am using JPA in my application. In one of the table, I have not used primary key (I know its a bad design).
Now the generated entity is as mentioned below :
#Entity
#Table(name="INTI_SCHEME_TOKEN")
public class IntiSchemeToken implements Serializable {
private static final long serialVersionUID = 1L;
#Column(name="CREATED_BY")
private String createdBy;
#Temporal( TemporalType.DATE)
#Column(name="CREATED_ON")
private Date createdOn;
#Column(name="SCH_ID")
private BigDecimal schId;
#Column(name="TOKEN_ID")
private BigDecimal tokenId;
public IntiSchemeToken() {
}
public String getCreatedBy() {
return this.createdBy;
}
public void setCreatedBy(String createdBy) {
this.createdBy = createdBy;
}
public Date getCreatedOn() {
return this.createdOn;
}
public void setCreatedOn(Date createdOn) {
this.createdOn = createdOn;
}
public BigDecimal getSchId() {
return this.schId;
}
public void setSchId(BigDecimal schId) {
this.schId = schId;
}
public BigDecimal getTokenId() {
return this.tokenId;
}
public void setTokenId(BigDecimal tokenId) {
this.tokenId = tokenId;
}
}
Here In my project, eclipse IDE shows ERROR mark(RED colored cross) on this class and the error is "The entity has no primary key attribute defined".
Can anyone tell me, How to create an entity without primary key ?
Thanks.
You can't. An entity MUST have a unique, immutable ID. It doesn't have to be defined as a primary key in the database, but the field or set of fields must uniquely identify the row, and its value may not change.
So, if one field in your entity, or one set of fields in your entity, satisfies these criteria, make it (or them) the ID of the entity. For example, if there is no way that a user can create two instances in the same day, you could make [createdOn, createdBy] the ID of the entity.
Of course this is a bad solution, and you should really change your schema and add an autogenerated, single-column ID in the entity.
If your Primary Key(PK) is a managed super class which is inherited in an entity class then you will have to include the mapped super class name in the persistence.xml file.
Look at the bug report:
https://bugs.eclipse.org/bugs/show_bug.cgi?id=361042
If you need to define a class without primary key, then you should mark that class as an Embeddable class. Otherwise you should give the primary key for all entities you are defining.
You can turn off (change) validation that was added.
Go to workspace preferences 'Java Persistence->JPA->Errors/Warnings' next 'Type' and change 'Entity has no primary key' to 'Warnning'.
In addition to http://en.wikibooks.org/wiki/Java_Persistence/Identity_and_Sequencing#No_Primary_Key you can use some build-in columns like ROWID in Oracle:
Oracle legacy table without good PK: How to Hibernate?
but with care:
http://www.orafaq.com/wiki/ROWID
Entity frameworks doesn't work for all kind of data (like statistical data which was used for analysis not for querying).
Another solution without Hibernate
If
- you don't have PK on the table
- there is a logical combination of columns that could be PK (not necessary if you can use some kind of rowid)
-- but some of the columns are NULLable so you really can't create PK because of DB limitation
- and you can't modify the table structure (would break insert/select statements with no explicitly listed columns at legacy code)
then you can try the following trick
- create view at database with virtual column that has value of concatenated logical key columns ('A='||a||'B='||'C='c..) or rowid
- create your JPA entity class by this view
- mark the virtual column with #Id annotation
That's it. Update/delete data operations are also possible (not insert) but I wouldn't use them if the virtual key column is not made of rowid (to avoid full scan searches by the DB table)
P.S. The same idea is partly described at the linked question.
You need to create primary key ,If not found any eligible field then create auto increment Id.
CREATE TABLE fin_home_loan (
ID int NOT NULL AUTO_INCREMENT,
PRIMARY KEY (ID));
Just add fake id field.
In Postgres:
#Id
#Column(name="ctid")
String id;
In Oracle:
#Id
#Column(name="ROWID")
String rowid;