I would like to persist my POJOs using Hibernate into a MySql database by first trying to "update", then "flush", then check the number of rows updated, then do an insert if that number was 0.
I chose the sequence above because my objects will be typically already present in the database, in which case I want to update them.

I realize I can do this with an HQL query, e.g.
int numRowsUpdated = session.createQuery("update Account a set ... a long list of fields ... where a.compositePkPart1=:compositePkPart1 and a.compositePkPart2=compositePkPart2")
.setString(....)
.... a long list of setters...
.setString("compositePkPart1 ", ...)
.setString("compositePkPart2", ...)
.executeUpdate();
if(numRowsUpdated==0) {
session.save(account);
}

Unfortunately my "Account" object is quite complex, has many attributes, has sub-classes (represented by "joined-subclass" in the hibernate mapping) with many attributes, so the code fragment above would look more like 500 lines of code (haven't written it yet).

So my question is:
Is there an easier way (shorter code) to do this?
I cannot use "session.update(account)", because it does not return the number of rows updated.
Maybe there is a way to write an HQL "update" query that is short and that can update all attributes of my object? e.g.
int numRowsUpdated = session.createQuery("update Account a set a=:a where a.compositePkPart1=:compositePkPart1 and a.compositePkPart2=compositePkPart2")
.setEntity(a, account)
.setString("compositePkPart1 ", ...)
.setString("compositePkPart2", ...)
.executeUpdate();
I tried this without success...

I appreciate your input.
Thank you,
-Ivan

Me again:
I want to clarify that my "Account" has a composite primary key (composed of two string-s);
The related hibernate mapping for "Account is:
<composite-id mapped="true" >
<key-property name="compositePkPart1" column="compositePkPart1" type="string" />
<key-property name="compositePkPart2" column="compositePkPart2" type="string" />
</composite-id>
Before calling update, my Account-s already have the compositePkPart1 and compositePkPart2 populated (they do not come from a db. sequence).

I am reading about "versioning" in Hibernate - Perhaps with "versioning" I can instruct Hibernate to do an SQL update followed by insert just by calling session.save(account) ? How do I achieve this?

Thanks,
-Ivan

Hibernate doesn't have many fancy batch updates and other batch processing. I guess it was not their goal to begin with.
Try using session.load() it can give u a lazy proxy (so that u don't have to incur the time consuming setting of all properties). Then set any property that u intend to update and save.

Me again.
I came-up with the following approach which I can not get to work perfectly - see the code comments below:
try {
session.load(Account.class, account);
// Try to SQL update an existing record in the db. that has the same PK:
session.update(account);
session.flush();
} catch(org.hibernate.StaleStateException e) {
// The update() above didn't find any record. Do an SQL insert:
// Note: The call to save() below should generate only SQL insert statements.
// However, it generates also some update-s and delete-s - don't know why.
// What should I do to get it to generate only insert-s? Calling session.evict(account) does not help...
session.flush();
//}
}

It's not possible to rely on exceptions thrown by a session like this. Read http://docs.jboss.org/hibernate/stable/ ... exceptions

I suggest that you use session.merge(). It should give you the desired behavior. See http://docs.jboss.org/hibernate/stable/ ... veorupdate

I tried "session.merge()", and it didn't work for me, as it generated many "select" sql statements, which I don't want.
I want to end-up with efficient SQL queries: the code should do an SQL update first, and only if that update returned 0 rows, it should do an SQL insert (I could write this code easily in JDBC). No "select" queries are needed.

Any other suggestion?

-Ivan

session.load(Account.class,account)??

What are u trying to do?
What is "account"?
I was expecting something like
Account account = (Account) session.load(Account.class, acNo);

As for merge, it will create a new entity in the db if one doesn't exist otherwise update the existing one. But I thought the original question was how to only update selected properties without fully initializing an entity in case it existed.