DynamoDBMappingException: no mapping for HASH key - java

When writing a DynamoDB Java App you can receive the 'no mapping for HASH key' error when writing or retrieving from a table if the table and its data model are not configured correctly. The full exception would be similar to:
com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMappingException: <YourClassNameHere>; no mapping for HASH key

Make sure that your annotated mapped class's getters are declared public.

Two helpful things to check here:
1) For your main setter for your hash key value make sure that the #DynamoDBHashKey notation is correctly set. #DynamoDBAttribute is NOT the correct one to use for your table's main hash key and neither is #DynamoDBIndexHashKey.
2) Make sure that the hash key is defined in the table definition:
CreateTableRequest createTableRequest = new CreateTableRequest()
.withTableName("testtable")
.withKeySchema(
new KeySchemaElement("id", KeyType.HASH)
)
.withProvisionedThroughput(new ProvisionedThroughput(1L, 1L))
.withAttributeDefinitions(
new AttributeDefinition("id", "S")
);
CreateTableResult result = amazonDynamoDB.createTable(createTableRequest);
The above table definition creates a table 'testtable' with a main index or hash key variable titled id and the type is S for string.
Additionally, if you are using inheritance, make sure that you don't have two functions with the same name that override each other. Dynamo will use the top-level getter and this can cause issues.

If you are using #Data annotation (lombok.data), Try again after removing it and generate getters and setters for all the Attributes(including the primary_key/partition_key).

Related

org.springframework.orm.jpa.JpaSystemException: identifier of an instance of com.cc.domain.User was altered from 90 to null; [duplicate]

org.hibernate.HibernateException: identifier of an instance
of org.cometd.hibernate.User altered from 12 to 3
in fact, my user table is really must dynamically change its value, my Java app is multithreaded.
Any ideas how to fix it?
Are you changing the primary key value of a User object somewhere? You shouldn't do that. Check that your mapping for the primary key is correct.
What does your mapping XML file or mapping annotations look like?
You must detach your entity from session before modifying its ID fields
In my case, the PK Field in hbm.xml was of type "integer" but in bean code it was long.
In my case getters and setter names were different from Variable name.
private Long stockId;
public Long getStockID() {
return stockId;
}
public void setStockID(Long stockID) {
this.stockId = stockID;
}
where it should be
public Long getStockId() {
return stockId;
}
public void setStockId(Long stockID) {
this.stockId = stockID;
}
In my case, I solved it changing the #Id field type from long to Long.
In my particular case, this was caused by a method in my service implementation that needed the spring #Transactional(readOnly = true) annotation. Once I added that, the issue was resolved. Unusual though, it was just a select statement.
Make sure you aren't trying to use the same User object more than once while changing the ID. In other words, if you were doing something in a batch type operation:
User user = new User(); // Using the same one over and over, won't work
List<Customer> customers = fetchCustomersFromSomeService();
for(Customer customer : customers) {
// User user = new User(); <-- This would work, you get a new one each time
user.setId(customer.getId());
user.setName(customer.getName());
saveUserToDB(user);
}
In my case, a template had a typo so instead of checking for equivalency (==) it was using an assignment equals (=).
So I changed the template logic from:
if (user1.id = user2.id) ...
to
if (user1.id == user2.id) ...
and now everything is fine. So, check your views as well!
It is a problem in your update method. Just instance new User before you save changes and you will be fine. If you use mapping between DTO and Entity class, than do this before mapping.
I had this error also. I had User Object, trying to change his Location, Location was FK in User table. I solved this problem with
#Transactional
public void update(User input) throws Exception {
User userDB = userRepository.findById(input.getUserId()).orElse(null);
userDB.setLocation(new Location());
userMapper.updateEntityFromDto(input, userDB);
User user= userRepository.save(userDB);
}
Also ran into this error message, but the root cause was of a different flavor from those referenced in the other answers here.
Generic answer:
Make sure that once hibernate loads an entity, no code changes the primary key value in that object in any way. When hibernate flushes all changes back to the database, it throws this exception because the primary key changed. If you don't do it explicitly, look for places where this may happen unintentionally, perhaps on related entities that only have LAZY loading configured.
In my case, I am using a mapping framework (MapStruct) to update an entity. In the process, also other referenced entities were being updates as mapping frameworks tend to do that by default. I was later replacing the original entity with new one (in DB terms, changed the value of the foreign key to reference a different row in the related table), the primary key of the previously-referenced entity was already updated, and hibernate attempted to persist this update on flush.
I was facing this issue, too.
The target table is a relation table, wiring two IDs from different tables. I have a UNIQUE constraint on the value combination, replacing the PK.
When updating one of the values of a tuple, this error occured.
This is how the table looks like (MySQL):
CREATE TABLE my_relation_table (
mrt_left_id BIGINT NOT NULL,
mrt_right_id BIGINT NOT NULL,
UNIQUE KEY uix_my_relation_table (mrt_left_id, mrt_right_id),
FOREIGN KEY (mrt_left_id)
REFERENCES left_table(lef_id),
FOREIGN KEY (mrt_right_id)
REFERENCES right_table(rig_id)
);
The Entity class for the RelationWithUnique entity looks basically like this:
#Entity
#IdClass(RelationWithUnique.class)
#Table(name = "my_relation_table")
public class RelationWithUnique implements Serializable {
...
#Id
#ManyToOne
#JoinColumn(name = "mrt_left_id", referencedColumnName = "left_table.lef_id")
private LeftTableEntity leftId;
#Id
#ManyToOne
#JoinColumn(name = "mrt_right_id", referencedColumnName = "right_table.rig_id")
private RightTableEntity rightId;
...
I fixed it by
// usually, we need to detach the object as we are updating the PK
// (rightId being part of the UNIQUE constraint) => PK
// but this would produce a duplicate entry,
// therefore, we simply delete the old tuple and add the new one
final RelationWithUnique newRelation = new RelationWithUnique();
newRelation.setLeftId(oldRelation.getLeftId());
newRelation.setRightId(rightId); // here, the value is updated actually
entityManager.remove(oldRelation);
entityManager.persist(newRelation);
Thanks a lot for the hint of the PK, I just missed it.
Problem can be also in different types of object's PK ("User" in your case) and type you ask hibernate to get session.get(type, id);.
In my case error was identifier of an instance of <skipped> was altered from 16 to 32.
Object's PK type was Integer, hibernate was asked for Long type.
In my case it was because the property was long on object but int in the mapping xml, this exception should be clearer
If you are using Spring MVC or Spring Boot try to avoid:
#ModelAttribute("user") in one controoler, and in other controller
model.addAttribute("user", userRepository.findOne(someId);
This situation can produce such error.
This is an old question, but I'm going to add the fix for my particular issue (Spring Boot, JPA using Hibernate, SQL Server 2014) since it doesn't exactly match the other answers included here:
I had a foreign key, e.g. my_id = '12345', but the value in the referenced column was my_id = '12345 '. It had an extra space at the end which hibernate didn't like. I removed the space, fixed the part of my code that was allowing this extra space, and everything works fine.
Faced the same Issue.
I had an assosciation between 2 beans. In bean A I had defined the variable type as Integer and in bean B I had defined the same variable as Long.
I changed both of them to Integer. This solved my issue.
I solve this by instancing a new instance of depending Object. For an example
instanceA.setInstanceB(new InstanceB());
instanceA.setInstanceB(YOUR NEW VALUE);
In my case I had a primary key in the database that had an accent, but in other table its foreign key didn't have. For some reason, MySQL allowed this.
It looks like you have changed identifier of an instance
of org.cometd.hibernate.User object menaged by JPA entity context.
In this case create the new User entity object with appropriate id. And set it instead of the original User object.
Did you using multiple Transaction managers from the same service class.
Like, if your project has two or more transaction configurations.
If true,
then at first separate them.
I got the issue when i tried fetching an existing DB entity, modified few fields and executed
session.save(entity)
instead of
session.merge(entity)
Since it is existing in the DB, when we should merge() instead of save()
you may be modified primary key of fetched entity and then trying to save with a same transaction to create new record from existing.

How do I reference Postgres constraints in j00q?

Using jooq 3.11.8, referencing a constraint in an onConflictOnConstraint is not particularly discoverable, and the documentation is exactly no help. I know the name of the constraint, but onConflictOnConstraint doesn't take a String.
Specifically:
ctx.insertInto(
TABLE,
TABLE.ID,
TABLE.FIELD1
)
.values(
id,
value
)
.onConflictOnConstraint(/* WHAT GOES HERE? */)
.doUpdate()
.set(TABLE.FIELD1, value)
.execute();
What am I missing?
There are 3 overloads of this method:
onConflictOnConstraint(Constraint): Use this with constraints defined through DSL.constraint(), i.e. the DDL API
onConflictOnConstraint(Name): Use this with DSL.name(), a way to create ad hoc identifier references
onConflictOnConstraint(UniqueKey): Use this with generated UniqueKey references in generated tables, e.g. as obtained from Table.getPrimaryKey()

How to use CacheConfiguration.setIndexedTypes for Ignite Cache

I am following the code for the running SQL queries in the Ignite cache, but am able to fully realize the use of the CacheConfiguration.setIndexedTypes API.
I am following the only help that I could find at the ignite site.
The documentation here says to use
CacheConfiguration.setIndexedTypes(MyKey.class, MyValue.class).
Now lets say in the Person class
#QuerySqlField(index = true)
private long id;
#QuerySqlField
private String firstName;
Which are the parameters that I should be passing in the setIndexedType method?
setIndexedTypes takes an even number of parameters. Every odd parameter corresponds to a key type, and every even - to a value type. In your case you should probably use id parameter as a key, so you should call it this way:
cacheConfig.setIndexedTypes(Long.class, Person.class);
Javadoc for setIndexedTypes method contains a pretty good explanation of this method: https://ignite.apache.org/releases/latest/javadoc/org/apache/ignite/configuration/CacheConfiguration.html#setIndexedTypes(java.lang.Class...)
UPD:
There will be registered a table in SQL for each pair of parameters that you provide to setIndexedTypes method.
Your SQL entities will map to cache records and they will have _key and _val columns in addition to the ones that you configured as QuerySqlField-s. So, you should specify types of keys and values that will be used in cache for each table.
You can refer to this page for more information: https://apacheignite.readme.io/docs/dml#basic-configuration
In your case it will be
cacheConfig.setIndexedTypes(KeyType.class, Person.class)
where KeyType is the type you use for keys while calling cache.put(key, person) or insert into Person(_key, ...) ...
Please refer to this documentation section

Return Hibernate envers Audit revision with modified flags

I'm using Hibernate Envers in my app to track changes in all fields of my entities.
I'm using #Audited(withModifiedFlag=true) annotation to do it.
The records are been correcty recorded at database and the _mod fields correctly indicate the changed fields.
I want to get a particular revision from some entity and the information of what fields have been changed. I'm using the follow method to do it:
List<Object[]> results = reader.createQuery()
.forRevisionsOfEntity(this.getDao().getClazz(), false, true)
.add(AuditEntity.id().eq(id))
.getResultList();
This method returns an list of an object array with my entity as first element.
The problem is that the returned entity doesn't have any information about the changed fields. So, my question is: how to get the information about the changed fields?
I know that this question is a bit old now but I was trying to do this and didn't really find any answers.
There doesn't seem to be a nice way to achieve this, but here is how I went about it.
Firstly you need to use projections, which no longer gives you a nice entity model already mapped for you. You'll still get back an array of Objects but each object in the array corresponds to each projection that you added (in order).
final List<Object[]> resultList = reader.createQuery()
.forRevisionsOfEntity(this.getDao().getClazz(), false, true)
// if you want revision properties like revision number/type etc
.addProjection(AuditEntity.revisionNumber())
// for your normal entity properties
.addProjection(AuditEntity.id())
.addProjection(AuditEntity.property("title")) // for each of your entity's properties
// for the modification properties
.addProjection(new AuditProperty<Object>(new ModifiedFlagPropertyName(new EntityPropertyName("title"))))
.add(AuditEntity.id().eq(id))
.getResultList();
You then need to map each result manually. This part is up to you, but I'm use a separate class as a revision model as it contains extra data to the normal entity data. If you wanted you could probably achieve this with #Transient properties on your entity class though.
final List<MyEntityRevision> results = resultList.stream().map(this::transformRevisionResult)
.collect(Collectors.toList());
private MyEntityRevision transformRevisionResult(Object[] revisionObjects) {
final MyEntityRevision rev = new MyEntityRevision();
rev.setRevisionNumber((Integer) revisionObjects[0]);
rev.setId((Long) revisionObjects[1]);
rev.setTitle((String) revisionObjects[2]);
rev.setTitleModified((Boolean) revisionObjects[3]);
return rev;
}

Custom defined column name for JSONObject key

I have a JSONObject in which I am putting keys and values from columns in my database. I want the key name to show up as a custom defined name, while I have it equivalent to the column name in the DB. How do I do this?
For eg, I have -
myObj.put(resultSet.getString(personId), personCarInfo);
While I want it to be -
myObj.put("personId", personCarInfo);
In JDBC, you can query the name of a column using the ResultSets meta data:
String columnName = resultSet.getMetaData().getColumnName(columnIndex);
String columnValue = resultSet.getString(columnIndex); // assuming, its a string
myObj.put(columnName, columnValue);
If I understood you correctly, you want to have mapping between column names and your custom defined names.
You could create simple one-directional mapping using statically initialized hashMap or by using enums.
If you want bi-directional mapping (i.e. be able to restore your table column name string from custom "personId" string) you could use Guava BiMap, for example.
Hope that helps.

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