I have a JPA question.
Let's say I have an entity set up as followed (only a hypothetical).
#Entity
#Table (name = "TESTTABLE")
public class TestTable {
#Id
#Basic (optional = false)
private String id;
#JoinColumn(name="TESTID", referencedColumnName = "ID")
#OneToOne(optional = true)
private TestTable testId;
}
Basically,
--=--=--=---=----
|TestTable....... |
--=--=--=---=----
| String id..........|<-----------------------|
| String testId....|-----------TestId = id |
--=--=--=--=--=-=
I have foreign_key constraints set up in the DB and, codewise, I am expecting the normal "integrity constraint violated - parent key not found" constraint to be returned if the value entered for the testId does not have a corresponding id value in TestTable (so if the only entries I had were (1, null) and (2, 1), (3, 17) would result in failure).
However, when I try to persist an entry such as the forementioned (3, 17) to the database, I get an IllegalStateException error (because I have no CascadeType.PERSIST and I am trying to persist an object that does not exist in the db). I get that this is expected behavior, but is there anyway to bypass this and just let the database handle it (and thus return the expected constraint)?
Thanks.
Just use cascade PERSIST in the relationship.
In EclipseLink you can also use the persistence unit property,
"eclipselink.persistence-context.commit-without-persist-rules"="true"
Related
I have a table with 3 columns
UUID - A UUID that is the primary key of the table
ID - A human readable ID of the resource (for a new resource, the ID should be automatically generated by a sequence)
Version - A version number
I am using JPA.
The table can contain multiple records with the same "human readable" ID and different versions.
I would like to be able to insert a new record without specifying the ID: the database should generate the ID automatically.
At the same time, when I need to insert a new version of the same resource, I would like to be able to insert a new row specifying the ID.
I have created a table where the UUID is the primary key, ID is defined as "integer generated by default as identity" and version is just an integer.
Using SQL query I can do what I want, but I do not know how to do it using JPA.
If I define the column as:
#Column(name="ID", insertable = false, updatable = false, nullable = false)
I can insert new records but the ID is always generated as new even if the resource already has one because the insert does not include the column.
If I define the column as:
#Column(name="ID", insertable = true, updatable = false, nullable = false)
The insert include the column and I am able to insert new rows specifying the ID but I cannot insert a row without the ID because the SQL generated is passing a null value for that column.
UPDATE
I have modified the configuration adding the annotation #Generated:
#Generated(value = GenerationTime.INSERT)
#Column(name="ID", updatable = false, nullable = false)
private Integer id;
With this, I am having the same problem: if I pass a value for id, the database is still generating a new one.
You can try to use #DynamicInsert annotation.
Assuming that you have the following table:
create table TST_MY_DATA
(
dt_id uuid,
dt_auto_id integer generated by default as identity,
dt_version integer,
primary key(dt_id)
);
Appropriate entity will look like this:
#Entity
#Table(name = "TST_MY_DATA")
#DynamicInsert
public class TestData
{
#Id
#GeneratedValue
#Column(name = "dt_id")
private UUID id;
// Unfortunately you cannot use #Generated annotation here,
// otherwise this column will be always absent in hibernate generated insert query
// #Generated(value = GenerationTime.INSERT)
#Column(name = "dt_auto_id")
private Long humanReadableId;
#Version
#Column(name = "dt_version")
private Long version;
// getters/setters
}
and then you can persist entities:
TestData test1 = new TestData();
session.persist(test1);
TestData test2 = new TestData();
test2.setHumanReadableId(27L);
session.persist(test2);
session.flush();
// here test1.getHumanReadableId() is null
/*
* You can use session.refresh(entity) only after session.flush() otherwise you will have:
* org.hibernate.UnresolvableObjectException: No row with the given identifier exists:
* [this instance does not yet exist as a row in the database#ff09c202-cd17-4d4a-baea-057e475fabb9]
**/
session.refresh(test1);
// here you can use the test1.getHumanReadableId() value fetched from DB
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 two Entities related by a ManyToMany and I want to select them via a named Query. This works in my test (with a H2 DB set up) and throws exceptions at runtime (with postgresql set up). Other than the H2 and PG I am hard pressed to find differences between test and production.
The Entities and the Query look like so (abbreviated):
#Entity(name = "Enrichment")
#Table(name = "mh_Enrichment")
NamedQueries({
#NamedQuery(name = "findByLink",
query = "SELECT e FROM Enrichment e INNER JOIN e.links l WHERE l.link in (:links)") })
public class EnrichmentImpl {
#Id
#Column(name = "enrichmentId")
#GeneratedValue(strategy = GenerationType.AUTO)
private long id;
#ManyToMany
#JoinTable(name = "mh_EnrichmentLinks", joinColumns = { #JoinColumn(name = "EnrichmentId",
referencedColumnName = "enrichmentId") }, inverseJoinColumns = { #JoinColumn(name = "Link",
referencedColumnName = "link") })
private List<Link> links;
}
#Entity(name = "Link")
#Table(name = "mh_enrichment_link")
public class LinksImpl {
#Id
#Column(name = "link", length = 1024)
private String link;
}
Upon running the query with a String value in production I get:
Internal Exception: org.postgresql.util.PSQLException: ERROR: operator does not exist: character varying = bigint
Hinweis: No operator matches the given name and argument type(s). You might need to add explicit type casts.
Position: 215
Error Code: 0
Call: SELECT t1.enrichmentId FROM mh_enrichment_link t0, mh_EnrichmentLinks t2, mh_Enrichment t1 WHERE ((t0.link IN (?)) AND ((t2.EnrichmentId = t1.enrichmentId) AND (t0.link = t2.Link)))
Any ideas what's wrong? It is the query, isn't it?
The query is supposed to retrieve a list of Enrichments that are related to the given link.
Update #1
As requested: the tables in the DB look as follows:
For entity Link
CREATE TABLE mh_enrichment_link
(
link character varying(1024) NOT NULL,
CONSTRAINT mh_enrichment_link_pkey PRIMARY KEY (link)
)
For entity Enrichment
CREATE TABLE mh_enrichment
(
enrichmentid bigint NOT NULL,
CONSTRAINT mh_enrichment_pkey PRIMARY KEY (enrichmentid)
)
For the relation (See answer, this was where it went wrong)
CREATE TABLE mh_enrichmentlinks
(
link character varying(1024) NOT NULL,
CONSTRAINT mh_enrichment_link_pkey PRIMARY KEY (link)
)
The issue was fixed by dropping all related tables and having JPA regenerate them. Table definitions didn't match Entity definitions.
Thats also the quite obviously the reason why the test worked and the production didn't. In testing the tables are generated on runtime, in production they existed already (with an outdated definition).
Side note: The query is correct and does what it should.
EclipseLink seems to be incorrectly passing a null primary key value to Derby when persisting into a table with generated primary key. Derby returns error of Attempt to modify an identity column in this case. Derby needs a SQL statement that excludes the id value. My question is how do I coerce EclipseLink to send the right SQL? Details follow...
I am using Eclipselink to map to a Derby database (v10.8.1.2) under the latest Netbeans 7.3beta2.
The database table primary key is auto generated:
CREATE TABLE STUDENT_BATCH (
ID bigint PRIMARY KEY
GENERATED ALWAYS AS IDENTITY (START WITH 1, INCREMENT BY 1),
FILENAME varchar(200) NOT NULL,
SCHOOLBOARD varchar(100) NOT NULL,
CREATE_TS timestamp NOT NULL,
CONTACT_INFO varchar(200),
NOTES varchar(2000),
BOARD_NAME varchar(100)
)
;
The corresponding jpa class specifies that the id is generated using strategy of identity:
#Entity
#Table(name = "STUDENT_BATCH")
#XmlRootElement
#NamedQueries({
#NamedQuery(name = "StudentBatch.findAll", query = "SELECT s FROM StudentBatch s")})
public class StudentBatch implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
#Column(name = "ID")
private Long id;
#Basic(optional = false)
#Column(name = "FILENAME")
private String filename;
#Basic(optional = false)
#Column(name = "SCHOOLBOARD")
private String schoolboard;
#Basic(optional = false)
#Column(name = "CREATE_TS")
#Temporal(TemporalType.TIMESTAMP)
private Date createTs;
#Column(name = "CONTACT_INFO")
private String contactInfo;
#Column(name = "NOTES")
private String notes;
#Column(name = "BOARD_NAME")
private String boardName;
#OneToMany(cascade = CascadeType.ALL, mappedBy = "studentBatchId")
private Collection<StudentRecord> studentRecordCollection;
methods etc follow...
When I go to persist the class, I do not specify an id so that Derby will provide the id.
StudentBatch sb = new StudentBatch();
sb.setBoardName(meta.get("BOARD NAME"));
sb.setContactInfo(meta.get("CONTACT INFO"));
sb.setCreateTs(new Date());
sb.setFilename(event.getFile().getFileName());
sb.setNotes(meta.get("NOTES"));
sb.setSchoolboard(meta.get("SCHOOL BOARD"));
_logger.debug("persisting batch");
em.persist(sb);
_logger.debug("flushing");
em.flush();
_logger.debug("flushed");
Eclipselink, however, passes the id to derby as null and Derby gives error Attempt to modify an identity column:
INFO: DEBUG 11710 27 Nov 2012 18:17:10,558 [http-thread-pool-8080(4)] (FileUploadController.java:75) - persisting batch
INFO: DEBUG 11713 27 Nov 2012 18:17:10,561 [http-thread-pool-8080(4)] (FileUploadController.java:77) - flushing
WARNING: Local Exception Stack:
Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.3.2.v20111125-r10461): org.eclipse.persistence.exceptions.DatabaseException
Internal Exception: java.sql.SQLSyntaxErrorException: Attempt to modify an identity column 'ID'.
Error Code: -1
Call: INSERT INTO STUDENT_BATCH (ID, BOARD_NAME, CONTACT_INFO, CREATE_TS, FILENAME, NOTES, SCHOOLBOARD) VALUES (?, ?, ?, ?, ?, ?, ?)
bind => [7 parameters bound]
Query: InsertObjectQuery(ca.ontario.mhltc.studentupload.model.StudentBatch[ id=null ])
at org.eclipse.persistence.exceptions.DatabaseException.sqlException(DatabaseException.java:333)
This makes some sense to me since if I try to execute an insert on sql command line with the id field specified I get an error too.
INSERT INTO STUDENT_BATCH (id, BOARD_NAME, CONTACT_INFO, CREATE_TS, FILENAME, NOTES, SCHOOLBOARD)
VALUES (null, 'abc', 'def', current_timestamp, 'aaa', 'aabb', '1234');
gives me this:
Error code -1, SQL state 42Z23: Attempt to modify an identity column 'ID'.
Line 1, column 1
Execution finished after 0 s, 1 error(s) occurred.
however, this insert statement is successful:
INSERT INTO STUDENT_BATCH (BOARD_NAME, CONTACT_INFO, CREATE_TS, FILENAME, NOTES, SCHOOLBOARD)
VALUES ('abc', 'def', current_timestamp, 'aaa', 'aabb', '1234');
returns
Executed successfully in 0.002 s, 1 rows affected.
Line 1, column 1
Execution finished after 0.002 s, 0 error(s) occurred.
Seems to me that Eclipselink should know about how Derby handles identity columns and should not pass the id column at all on the insert statement. Is there a workaround for this or I should I just dump Derby and use some other database?
EclipseLink does not include the Id in the INSERT for Derby IDENTITY, so you have something odd going on.
Did you previously use another generator strategy and not recompile/deploy your code correctly?
Also try setting your platform using the"eclipselink.target-database"="Derby" in your persistence.xml.
I am trying to create two entities where both entities have embeddedIds. One of the entities have 2 references to the other entity, where both of those references are related as ManyToOne.
Example codes are written below;
#Embeddable
public class ItemPK {
#Column(nullable = false, length = 100)
private String itemId;
#Column(name = "item_client_id", nullable = false)
private int clientId;
...
}
#Entity
#Table(name = "item")
public class Item {
#EmbeddedId
private ItemPK id;
#ManyToOne
#JoinColumn(name = "item_client_id")
private Client client;
#OneToMany(mappedBy="item", cascade = CascadeType.ALL, orphanRemoval = true)
private Set<RelatedItem> relatedItems;
#OneToMany(mappedBy="relatedItem", cascade = CascadeType.ALL, orphanRemoval = true)
private Set<RelatedItem> relatedItemsRHS;
...
}
#Embeddable
public class RelatedItemPK {
#Column(name = "itemId", length = 100, nullable = false)
private String itemId;
#Column(name = "item_client_id", nullable = false)
private int clientId;
#Column(name = "relatedItemId", length = 100, nullable = false)
private String relatedItemId;
#Column(name = "related_item_client_id", nullable = false)
private int relatedItemClientId;
...
}
#Entity
#Table(name = "related_item")
public class RelatedItem {
#EmbeddedId
private RelatedItemPK id;
#ManyToOne(cascade = CascadeType.ALL, optional = false)
#JoinColumns({
#JoinColumn(name="itemId", referencedColumnName="itemId", insertable=false, updatable=false),
#JoinColumn(name="item_client_id", referencedColumnName="item_client_id", insertable=false, updatable=false)
})
private Item item;
#ManyToOne(cascade = CascadeType.ALL, optional = false)
#JoinColumns({
#JoinColumn(name="related_item_client_id", referencedColumnName="item_client_id", insertable=false, updatable=false),
#JoinColumn(name="relatedItemId", referencedColumnName="itemId", insertable=false, updatable=false)
})
private Item relatedItem;
...
}
The problem is while creating foreign keys for RelatedItem entity, I got an SQLException. It is the second ManyToOne relation that fails. The foreign key generation sql is below,
ALTER TABLE related_item ADD CONSTRAINT FK_related_item_related_item_client_id FOREIGN KEY (related_item_client_id, relatedItemId) REFERENCES item (item_client_id, itemId)
Since item table is indexed first by itemId then by item_client_id, this statement causes MySQL to produce an error.
I would like to switch the places of columns so that the SQL should look like the following,
ALTER TABLE related_item ADD CONSTRAINT FK_related_item_relatedItemId FOREIGN KEY (relatedItemId, related_item_client_id) REFERENCES item (itemId,item_client_id)
I tried changing the order of "JoinColumn"s but the result didn't change. I also tried renaming the fields to check if persistence provider choses the order by column name but again the result didn't change.
So, is there a way to enforce the column ordering?
p.s. I use following stuff:
MySQL 5.1
EclipseLink 2.0.0
Java EE 6
JPA 2
GlassFish v3
Edit: EclipseLink produces following SQL, which fails to run;
CREATE TABLE related_item (SIMILARITY DOUBLE, widget_id INTEGER NOT NULL, relatedItemId VARCHAR(100) NOT NULL, itemId VARCHAR(100) NOT NULL, related_item_client_id INTEGER NOT NULL, item_client_id INTEGER NOT NULL, PRIMARY KEY (widget_id, relatedItemId, itemId, related_item_client_id, item_client_id));
CREATE TABLE item (IMAGEURL VARCHAR(2048), STATUS VARCHAR(64), URL VARCHAR(2048), PRICE DOUBLE, STOCK INTEGER, DESCRIPTION TEXT(64000), NAME VARCHAR(255), ITEMID VARCHAR(100) NOT NULL, item_client_id INTEGER NOT NULL, PRIMARY KEY (ITEMID, item_client_id));
ALTER TABLE related_item ADD CONSTRAINT FK_related_item_itemId FOREIGN KEY (itemId, item_client_id) REFERENCES item (itemId, item_client_id);
ALTER TABLE related_item ADD CONSTRAINT FK_related_item_related_item_client_id FOREIGN KEY (related_item_client_id, relatedItemId) REFERENCES item (item_client_id, itemId);
ALTER TABLE item ADD CONSTRAINT FK_item_item_client_id FOREIGN KEY (item_client_id) REFERENCES client (ID);
Please include the stack trace. However, I strongly recommend you skip the #JoinColumn tags unless you have a VERY good reason for specifying the foreign keys yourself. By specifying the mappedBy attribute in one of the directions, JPA can figure out what to do by itself.
Java EE 6 and JPA put a lot of effort into enabling Convention over Configuration, which means that most of the time, things will work out of the box. It's desirable for you, the programmer because you have less boiler plate code to worry about, and it's desirable for the JPA and Jave EE container implementors because it gives them freedom to chose the best performing solutions. By declaring the foreign key relationships yourself, you rob both you and JPA of this advantage.
Edit: In fact, I suspect that both specifying mappedBy and specifying the #JoinTable could be the root cause of your problem. But I need to see the stack trace to tell for sure.
The order of the columns should not matter. If it does, then you could change the order in your index to match, or change the order you list your primary key in, or just use your scripts to generate your DDL.