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Hibernate Sequence generation in ms sql server

We are using #sequencegenerator annotations to generate sequence in mssql database but when we execute sequence is generated as table instead of sequence, we have used 2012Dialect but still we face same issue and application throws exception invalid object name - sequence name-. Please help with solution

Have you used GeneratedValue annotation to specify that the id generation value witll be from a database sequence?
example:
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "seq_name")
#SequenceGenerator(name = "seq_name", sequenceName = "seq_name_in_database", allocationSize = 1)
#Column(name = "id")
private Long id;

It seems that Hibernate (v 5.6.3) is using its own tables to manage sequences in sql server, you must create the table with the same name as your sequence with one column named next_val then insert a line with the init value.
Hibernate use the query to select :
select next_val as id_val from sequence_name with (updlock,rowlock)
then increment the next_val :
update sequence_utilisateur set next_val= ? where next_val=?
Also don't define the column for wich you use the generated value as IDENTITY.

Spring JPA - Hibernate: Batch insert execute too much select nextval (‘sequence’)

Now I'm trying to enhance performance of my web application, I use spring JPA 2.3.0- Hibernate 5.4.15.Final, Postgres 12 and manage transaction by #Transaction. The web app is deployed on aws beanstalk, run multiple instances at the same time, but the database instance is not scalable. And I use bigSerial type for ID of tables.
For instance, I have a STUDENTS table, ID is bigSerial and some other columns.
I got a problems when using
#GeneratedValue(strategy = GenerationType.IDENTITY)
,
Hibernate couldn't batch insert when saving a list of entities.
And I try to use
#GeneratedValue(strategy = GenerationType.AUTO, generator = "students_id_seq")
#SequenceGenerator(name = "students_id_seq", sequenceName = "students_id_seq")
hibernate.id.new_generator_mappings=false
hibernate.jdbc.batch_size=10
hibernate.order_inserts=true
hibernate.order_updates=true
hibernate.batch_versioned_data=true
It seem Hibernate could batch insert, but the problem is Hibernate execute select nextval ('students_id_seq') multiple times. If an entity list has 30 items, Hibernate execute select nextval 30 times, and 3 times for batch insert query.
Some statistics:
If using GenerationType.IDENTITY
save(entity):
insert into ... : execute once
saveAll(n entities)
insert into ... : execute n times
If using GenerationType.SEQUENCE/ GenerationType.AUTO
save(entity):
select nextval ('students_id_seq'): execute once
insert into ... : execute once
saveAll(n entities):
select nextval ('students_id_seq'): execute n times
insert into ... : execute n/batch_size times
In conclusion, If using GenerationType.AUTO or GenerationType.SEQUENCE with allocationSize = 1:
when insert one entity, application increases 100% times to execute
queries ( from one insert query only increase to 2 queries: select
nextval, and insert query )
when batch insert, application increase more than 10% if batch_size = 10
My question is, is there anyway to batch insert but not execute to many select nextval query ? Something likes GenerationType.IDENTITY, not execute select nextval, just batch insert and IDs will be handled by sequence in the database.
When I test with GenerationType.SEQUENCE and allocationSize=1 (GenerationType.AUTO), the application executes too much select nextval query, I think It is even worse than the IDENTITY strategy.
And for some reasons, I don't want to use allocationSize, it may lead to duplicate primary key error when run insert query manual or when migrate data or some other cases.
After some research, I found a way to get a value list of a sequence:
select nextval ('students_id_seq') from generate_series(1,10);
We can replace 10 by entityList.size() or number of entities doesn't have ID in the entityList when batch insert, just get enough to use, don't create too much gap between IDs, but I'm not sure whether or not Hibernate supported, if yes, please share me the documentation to reference.
Thank you
https://discourse.hibernate.org/t/batch-insert-execute-too-much-select-nextval-sequence/4232

What you are looking for is the HiLo algorithm for id generation.
For every id generated from a sequence it generates a number of ids on the client without accessing the database.
You configure it on your entity as this:
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "hilo_sequence_generator")
#GenericGenerator(
name = "hilo_sequence_generator",
strategy = "org.hibernate.id.enhanced.SequenceStyleGenerator",
parameters = {
#Parameter(name = "sequence_name", value = "hilo_seqeunce"),
#Parameter(name = "initial_value", value = "1"),
#Parameter(name = "increment_size", value = "3"),
#Parameter(name = "optimizer", value = "hilo")
})
#Id
private Long id;

I would say that I have some experience of that point. I was doing insertion for more than 128,000 records.
And my target was to enhance the time-consuming to do that. I would try to summarize the case as below :
The code did not use any persist() or save() methods. These records were saved when the #Transactionl method exits
I was using hibernate batch inserts below are the settings in the config map
spring.jpa.properties.hibernate.jdbc.batch_size: "40"
spring.jpa.properties.hibernate.order_inserts: "true"
spring.jpa.properties.hibernate.order_updates: "true"
spring.main.allow-bean-definition-overriding: "true"
I modified the allocation size in my entity Id configuration as below:
#Id
#GeneratedValue(strategy = GenerationType.SEQUENCE, generator ="mappingentry_sql_generator")
#SequenceGenerator(name = "mappingentry_sql_generator", sequenceName ="mappingentry_id_seq", allocationSize = 40)
private Long id;
Notes: I set the "allocationSize" in the sequence generator to be equal to the "batch_size" value in the setting
Also, I altered my sequence "mappingentry_id_seq" to increment by 40 as well
After doing these changes the time was reduced from 55 seconds to 20 seconds which was a great impact
The only thing that I did not understand is that when I checked the value of the id column that was generated by the sequence I did not find any value gap. Every ID value exceeded the previous by 1, not 40. That is what I am currently trying to understand

Unable to create record with GENERATED IDENTITY primary key using Ebean

I have a table in Oracle Database 12c, created with the following DDL:
create table customer (
id INTEGER GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
name VARCHAR(100)
);
I am trying to insert a row to this table using Ebean.save method with the model defined below:
#Entity
#Table(name = "customer")
public class Customer {
#Id
Integer id;
....
The code used to insert the row is as follows:
Customer customer = new Customer();
customer.setName(name);
Ebean.save(customer);
It is failing with the following stack trace:
Caused by: java.sql.SQLSyntaxErrorException: ORA-02289: sequence does not exist
at oracle.jdbc.driver.T4CTTIoer11.processError(T4CTTIoer11.java:494)
at oracle.jdbc.driver.T4CTTIoer11.processError(T4CTTIoer11.java:446)
at oracle.jdbc.driver.T4C8Oall.processError(T4C8Oall.java:1054)
at oracle.jdbc.driver.T4CTTIfun.receive(T4CTTIfun.java:623)
....
Caused by: Error : 2289, Position : 7, Sql = select
customer_seq.nextval, a from (select level as a FROM dual CONNECT BY level <= 20), OriginalSql = select customer_seq.nextval, a from (select level as a FROM dual CONNECT BY level <= 20), Error Msg = ORA-02289: sequence does not exist
From the error, what I understand is that Ebean is trying to use Sequence strategy for the identity column and it is failing. I've tried setting Identity strategy as follows without any success, maybe because Ebean is using Sequence strategy for Oracle DB as explained here.
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
Integer id;
Is there a way to save a row in a Oracle 12c table with autogenerated identity column as defined above with Ebean? Was I on the right track by setting the IDENTITY strategy?

This was a bug in Ebean, and is fixed in 11.10.1 release. The bug was reported on github following my post on Ebean's google group. I have verified that I can specify autogenerated identity column with this version of Ebean as follows:
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
Integer id;

Liquibase + Postgresql + Spring Jpa : Id auto increment issue

I have the following Id description in the entity:
#Id
#GeneratedValue(strategy= GenerationType.IDENTITY)
private Long id;
Liquibase instruction for generate this id is following :
<column name="id" autoIncrement="true" type="INT">
<constraints nullable="false" primaryKey="true" primaryKeyName="pk_entity"/>
</column>
Also I have liquibase scripts that insert to this table predefined values, e.g.
<insert tableName="entityTable" schemaName="public">
<column name="id">1</column>
<!- other fields-->
</insert>
The problem has appeared when I try to insert a new record without id using Jpa repository.
I got an error with a message like "duplicate id".
So, I understand that jpa(hibernate) doesn't use postgresql sequence for getting a new id value. And I don't want to include the sequence name to the entity's id description. I have hoped that this situation could be resolved by the postgresql itself.
And I wouldn't to use the 'hibernate_sequence'.
So, any idea how I can resolve this issue.
Thank you.

Liquibase's instruction autoIncrement="true" generates serial column for PostgreSQL. For serial column PostgreSQL will create a sequence with a name like tablename_colname_seq. Default column values will be assigned from this sequence.
But when you explicitly insert a value into serial column, it doesn't affect sequence generator, and its next value will not change. So it can generate a duplicate value, which is exactly your case.
To prevent this after you inserted explicit values you need to change the current value of a sequence generator either with ALTER SEQUENCE statement or with setval() function, e.g.:
ALTER SEQUENCE tablename_colname_seq RESTART WITH 42;
SELECT setval('tablename_colname_seq', (SELECT max(colname) FROM tablename));
This should fix the issue.

First create to table name example:
CREATE TABLE TABLE_NAME(ID_NAME SERIAL PRIMARY KEY NOT NULL);
Then in your annotation:
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long nameAtribute;

How / where does Oracle set / store #SequenceGenerator values

I have a standard JPA #SequenceGenerator annotated entity:
#Id
#Column(name = "ID", unique = true, nullable = false)
#GeneratedValue(generator = "mySeq", strategy = GenerationType.SEQUENCE)
#SequenceGenerator(name = "mySeq", sequenceName = "MY_SEQ", allocationSize = 10)
private long id;
with the named Oracle Sequence defined as:
CREATE SEQUENCE MY_SEQ
START WITH 55554444
INCREMENT BY 1
NOORDER NOCYCLE;
When I persist through a standard Java, Spring Data Service, the first persisted, generated ID value is:
555544440
In other words, it's * 10 what I had defined as a starting value.
Is this expected behaviour?
When I query:
select last_number from dba_sequences
though, the returned value is still of the 55554444 range.
Running an equivalent insert directly on the DB
INSERT INTO MY_TABLE (ID) VALUES (MY_SEQ.nextVal)
the ID value is generated and persisted as I would expect; i.e 55554444, 55554445, 55554446, etc. (and also correlates the last_number in dba_sequences)
Whats going on! How and why is the JPA persistence * 10 my sequence IDs!?
Stumped, any help appreciated!
thanks,
Damien

Hibernate, #SequenceGenerator and allocationSize answered this.
That is, if the JPA defined allocationSize differs from the oracle sequence increment size, bad things happen.
For me:
JPA allocationSize = 10
DB sequence increment = 1
Java persistence was then multiplying the oracle sequence * 10