Hi, I am trying to migrate from 4.3.6.Final to 5.1.0 Final to get java 8 date time api mapping and unrelated join entities features.
But unfortunately I got an issue related with sequence generation.
Here is my test:
{code}
for (int i = 0; i < 50; i++) {
Client client = new Client();
client.setName("Test#" + i);
clientRepository.save(client);
System.out.println(client.getId());
}
{code}
{code}
-----------------------------------------------------------------
@Entity
@Table(name = "client")
@Getter
@Setter
class Client {
@Id
@GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "c_seq")
@SequenceGenerator(name = "c_seq", sequenceName = "c_seq", allocationSize = 20)
@Column(name = "ID_CLIENT")
public Integer id;
....
}
{code}
*CREATE SEQUENCE c_seq start 1 increment 1;*
---------------------------------------------------------------------------------------------------------------------
Console output:
{code}
Hibernate:
select
nextval ('c_seq')
Hibernate:
select
nextval ('c_seq')
1,2
Hibernate:
select
nextval ('c_seq')
-16, -15, -14, -13, -12, -11, -10, -9, -8, -7, -6, -5, -4, -3, -2, -1, 0
org.springframework.dao.DataIntegrityViolationException: A different object with the same identifier value was already associated with the session : [igor.domain.Client#1]
This exception rises cause next id after 0 was 1 and we've already Client with id 1.
{code}
Actually you have changed sequence strategy generation in new 5.1.0 version
old: SequenceHiLoGenerator
new: SequenceStyleGenerator
And SequenceStyleGenerator uses PooledOptimizer.
I've spent time debugging PooledOptimizer and got that it happens due to this piece of code
{code}
else if ( generationState.value.gt( generationState.hiValue ) ) {
generationState.hiValue = callback.getNextValue();
generationState.value = generationState.hiValue.copy().subtract( incrementSize - 1 );
}
{code}
But it works fine with Hibernate 4.3.6.Final
Console output:
{code}
Hibernate:
select
nextval ('c_seq')
20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39,
Hibernate:
select
nextval ('c_seq')
40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59
Hibernate:
select
nextval ('c_seq')
60, 61, 62, 63, 64, 65, 66, 67, 68, 69
Hibernate:
/* insert igor.domain.Client
*/ insert
into
client
(age, name, id_client)
values
(?, ?, ?) (x50 times)
{code}
As we can see everything is fine, allocationSize works and there is no exception with 4.3.6.
I am really wondering about negative ids and this issue.
NOTE: If I change my sequence to CREATE SEQUENCE c_seq start 1 *increment 20*;
,increment size is the same as allocationSize, it works fine:
{code}
Hibernate:
select
nextval ('c_seq')
Hibernate:
select
nextval ('c_seq')
1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21
Hibernate:
select
nextval ('c_seq')
22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41
Hibernate:
select
nextval ('c_seq')
42, 43, 44, 45, 46, 47, 48, 49, 50
Hibernate:
/* insert igor.domain.Client
*/ insert
into
client
(age, NAME, ID_CLIENT)
values
(?, ?, ?) (x50 times)
{code}
It even better then in 4.3.6 cause id starts from 1, not from 20
|
|