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How to prevent select after insert in hibernate 3

We are using hibernate 3 to insert some values, just plain bean objects. However, this specific process does not have a SELECT privilege on the same table that it does the INSERT. So, what bothers us, is the SELECT statement that is done right after the INSERT. I am just guessing it is done to retrieve the generated ID and may be some other stuff. But, what if I in my code don't need that? Can I somehow state to hibernate 'just insert this entity and do not re-select the generated ID' ? The main point is that this table is only allowed to be inserted into by this user, but its not allowed for SELECT.
Thank you.

How to update existing entities with JpaItemWriter?

I'm using spring-batch jobs to persist content of a large csv file to a database.
JpaItemWriter is used for persistence, which is fine so far.
But now I'd like first to check if an entity already exists in the database (by id - the id field in csv and in database are equal), and in case just update the entity instead.
How could this be done?

When I needed to do this, the best I came up with was having my custom FieldSetMapper (used by the FlatFileItemReader) load the item from the database (or create a new instance of it doesn't exist) and then setting the properties based on the input. Since JpaItemWriter uses .merge, it will write the entity by updating if it was loaded from the database and insert if it was a new entity.
I also needed to have it run with a batch size of 1, to ensure that if there were duplicates in my input (which I did have), it would actually go one row at a time and insert or update for each one and not try to insert them all at once causing key problems.
As you might imagine, all this worked a lot slower than I would have liked. It queries the database for each and every row, and then does the corresponding update or insert. But as for my case it was for a monthly overnight batch process, it was good enough for our needs, even if it took many hours to run.

hibernate persist fails tries to create object with existing id

I am using spring-hibernate-postgres. I have a table say 'some_entity'. It already contains some records.
I have a program that tries to create new SomeEntity object. I am populating that object with appropriate properties, and afterwards I am calling persist() method on it.
In the log, I see that hibernate is trying to get nextVal() from the table sequences. But, nextval that my postgres returns is same as id of 2nd row of some_entity table. So, my hibernate tries to create row with that id. And hence my persist() fails with hibernate constraint violation exception.
May be I am not phrasing the question correctly. I hope someone has already encountered this problem and has resolution for it.
Thanks

I had this problem. I solved it through execution of sql, that updates sequence at application launch
ALTER SEQUENCE names_id_seq RESTART WITH currentId;
,where currentId I get from
SELECT currval('names_id_seq');

How to make update faster with Hibernate while using huge number of records

I am facing issue while using the hibernate update (Session.update()) portion with huge number of records. it is becoming very slower. but there is no issue with the insert (Session.insert()) portion. is there any way to do the update portion while we do update on lakh's of records.is there any way to tune the sql server so that the update will become faster. while we add seperate indexes to all the primary fields then the delete portion is taking time. is there any better way to tune sql server so that it performs well with insert, delete and update.
Thank you,
Saif.

do a batch update instead of individual update for each record. this way you will only hit the database once for all the records.

When you do a save only the data is saved into the database whereas when your updating a record it has to first perform the search operation and then update the record that is why your facing issues on update and not on save when your are handling huge number of records can use hibernate's BATCH PROCESSING to update your records. Here is a good link for batch processing in hibernate from tutorials point:
http://www.tutorialspoint.com/hibernate/hibernate_batch_processing.htm

There may be other solutions to this but one way I know is:
Whenever you save or update an instance through session (e.g. session.save(), session.update(), session.saveOrUpdate() etc.), it also updates the instance FK associations.
So if your POJO has multiple FK associations, it will fire queries on those tables as well.
So instead of updating instance in this way, I would suggest to use HQL (if it applies to your requirement) to save or update instance.

Workaround for Spring/Hibernate due to non-standard behaviour of UNIQUE constraint in MS SQL

There is a UNIQUE database constraint on an index which doesn't allow more than one record having identical columns.
There is a piece of code, managed by Hibernate (v2.1.8), doing two DAO
getHibernateTemplate().save( theObject )
calls which results two records entered into the table mentioned above.
If this code is executed without transactions, it results INSERT, UPDATE, then another INSERT and another UPDATE SQL statements and works fine. Apparently, the sequence is to insert the record containing DB NULL first, and then update it with the proper data.
If this code is executed under Spring (v2.0.5) wrapped in a single Spring transaction, it results two INSERTS, followed by immediate exception due to UNIQUE constraint mentioned above.
This problem only manifests itself on MS SQL due to its incompatibility with ANSI SQL. It works fine on MySQL and Oracle. Unfortunately, our solution is cross-platform and must support all databases.
Having this stack of technologies, what would be your preferred workaround for given problem?

You could try flushing the hibernate session in between the two saves. This may force Hibernate to perform the first update before the second insert.
Also, when you say that hibernate is inserting NULL with the insert, do you mean every column is NULL, or just the ID column?

I have no experience in Hibernate, so I don't know if you are free to change the DB at your will or if Hibernate requires a specific DB structure you cannot change.
If you can make changes then you can use this workaround in MSSQL tu emulate the ANSI behaviour :
drop the unique index/constraint
define a calc field like this:
alter table MyTable Add MyCalcField as
case when MyUniqueField is NULL
then cast(Myprimarykey as MyUniqueFieldType)
else MyUniqueField end
add the unique constraint on this new field you created.
Naturally this applies if MyUniqueField is not the primary key! :)
You can find more details in this article at databasejournal.com