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Log how many items have been impacted in a Spring/Hibernate transaction

I have this method that is called from another service:
#Transactional(propagation = Propagation.REQUIRES_NEW, rollbackFor = Exception.class)
public void execute(String sql) {
Query query = entityManager.createNativeQuery(sql);
query.executeUpdate();
}
Basically the client loads multiple sql files and run each sql file in a new transaction, in order to not impact other files execution.
For example this is an example of an sql file, that is cleaning up some data:
begin;
delete from table t where t.created_at < current_date - interval '2 month';
commit;
What I'm trying to do is to log, the outcome of each transaction. For example here, I want to display how many records were deleted. How can I do that from Spring ? I know that you can log something more specific with:
logging.level.org.springframework.transaction=TRACE
, but still I cannot see any outcome. This reveals information about sql that will run and when transaction started/ended.
Second solution was to check the result of:
int count = query.executeUpdate();
, but count is 0, even though the sql code got executed and deletes hundreds of rows.
Thanks upfront for the suggestions !

The problem is as #XtremeBaumer correctly pointed out your script. If you just run executeUpdate with a delete statement it will return the number of affected rows.
But that is not what you are doing. You are executing a code block delimited by begin and end. There might be a way for such a code block to return a value, but that would need to be coded into the code block and is probably highly database specific.

Hibernate OGM Mongodb Aggregate Query not working with JPA setFirstResult and setMaxResult while next Execution

I am using Hibernate OGM (5.2.0.Alpha1) with MongoDB (3.4)
While I am Executing
String query ="db.student.find({'collegeName' :'VNSGU'})"
for pagination With JPA setFirstResult() and setMaxResult(), It is working fine, but while executing aggregate Query
String query = "db.student.aggregate([{'$match' : {'collegeName' :'VNSGU'}}])";
List listOfStudent = entityManager.createNativeQuery(query, Student.class).setFirstResult(startPosition).setMaxResults(noOfRecords).getResultList();
Execution :
In database table, i have total 10 number of records where college name is
'VNSGU',
When startPosition = 0 and noOfRecords = 5, it will give my proper output on
first execution and return 5 records,
And when try to execute query second time where startPosition = 5 and
noOfRecords = 5, it will return empty list, because on second execution it
will have total 5 no of records which is an output of first Execution (i checked
it by executing query without setFirstResult() and setMaxResult() and returning
total 5 records).As Per, I understood the output of earlier execution will
become an input of next execution and it will return result from earlier
result.
But actually what is happening and What is the solution for this..??

So indeed, it is a bug.
We opened the following issue to track the bug you reported: https://hibernate.atlassian.net/browse/OGM-1411 .
A fix is under review, it will be part of the upcoming 5.3.1.Final release.

As Per, I understood the output of earlier execution will become an input of next execution and it will return result from earlier result.
I don't think that's the issue. More likely what's happening is that Hibernate OGM cached the result of the first query and it's returning it the second time as well. This seems related to this other problem: https://hibernate.atlassian.net/browse/OGM-1375
I'll update this answer as soon as I have investigate the issue further.

Hibernate query not returning correct value

So in my database, I have 3 rows, two rows have defaultFlag as 0 and one is set to 1, now in my processing am updating defaultProperty of one object to 1 from 0 but am not saving this object yet.
Before saving I need to query database and find if any row has defaultFlag set or not, there would be only 1 default set.
So before doing update am running query to find if default is set and i get 2 values out, note here if i go and check in db then there is only 1 row with default set but query gives me two result because this.object default property has changed from 0 to 1 but note that this object is not yet saved in database.
I am really confused here as to why hibernate query is returning 2 when there is one row with default set in database and other object whose default property has changed but it is not saved.
Any thoughts would be helpful. I can provide query if need be.
Update
Following suggestions, I added session.clear() to before running the query.
session.clear();
String sql = "SELECT * FROM BANKACCOUNTS WHERE PARTYID = :partyId AND CURRENCYID = :currencySymbol AND ISDEFAULTBANKACCOUNT= :defaultbankAccount";
SQLQuery q = session.createSQLQuery(sql);
q.addEntity(BankAccount.class);
q.setParameter("partyId", partyId);
q.setParameter("currencySymbol", currencySymbol);
q.setParameter("defaultbankAccount", 1);
return q.uniqueResult();
and it returns 1 row in result as expected but now am getting
nested exception is org.hibernate.NonUniqueObjectException: a different object with the same identifier value was already associated with the session exception

Either query which row has the "default flag" set before you start changing it, or query for a list of rows with default flag set & clear all except the one you're trying to set.
Very easy, stop mucking about with your "brittle" current approach which will break in the face of concurrency or if data is ever in an inconsistent state. Use a reliable approach instead, which will always set the data to a valid state.
protected void makeAccountDefault (BankAccount acc) {
// find & clear any existing 'Default Accounts', other than specified.
//
String sql = "SELECT * FROM BANKACCOUNTS WHERE PARTYID = :partyId AND CURRENCYID = :currencySymbol AND ISDEFAULTBANKACCOUNT= :defaultbankAccount";
SQLQuery q = session.createSQLQuery(sql);
q.addEntity(BankAccount.class);
q.setParameter("partyId", partyId);
q.setParameter("currencySymbol", currencySymbol);
q.setParameter("defaultbankAccount", 1);
//
List<BackAccount> existingDefaults = q.list();
for (BankAccount existing : existingDefaults) {
if (! existing.equals( acc))
existing.setDefaultBankAccount( false);
}
// set the specified Account as Default.
acc.setDefaultBankAccount( true);
// done.
}
This is how you write proper code, do it simple & reliable. Never make or depend on weak assumptions about the reliability of data or internal state, always read & process "beforehand state" before you do the operation, just implement your code clean & right and it will serve you well.

I think that your second query won't be executed at all because the entity is already in the first level cache.
As your transaction is not yet commited, you don't see the changes in the underlying database.
(this is only a guess)

That's only a guess because you're not giving many details, but I suppose that you perform your myObject.setMyDefaultProperty(1) while your session is open.
In this case, be careful that you don't need to actually perform a session.update(myObject) to save the change. It is the nominal case when database update is transparently done by hibernate.
So, in fact, I think that your change is saved... (but not commited, of course, thus not seen when you check in db)
To verify this, you should enable the hibernate.show_sql option. You will see if an Update statement is triggered (I advise to always enable this option in development phase anyway)

Java MySQL PreparedStatement.setBoolean wraps value in quotes

Short version of my question is:
PreparedStatement ps;
ps = connection.prepareStatement("Insert into T values (?)");
ps.setBoolean(1, true);
ps.executeUpdate();
What can be the reasons for this code sample to produce query with value wrapped in quotes?
Long version of my question is:
I have JavaEE application with plain JDBC for DB interactions and recently I noticed that there are some MySQLDataTruncation exceptions appearing in my logs. These exceptions were occurring on attempt to save entity into DB table which have boolean column defined as BIT(1). And it was because generated query looked like this:
Insert into T values ('1');
Note that value is wrapped with quotes. Query was logged from application with Log4J log.info(ps); statement.
Previous logs demonstrate that there where no quotes.
Furthermore, even MySQL server logs started to look different. Before this happened I had given pairs of records for each query executed:
12345 Prepare Insert into T values (?)
12345 Execute Insert into T values (1)
And after:
12345 Query Insert into T values ('1')
It is worth noting that those changes wasn`t a result of deploying new version of application or even restarting MySQL/Application server and code, responsible of query generation, is as straightforward as example in this question.
Application server restart fixed the issue for about 12 hours, and then it happened again. As a temporary solution I changed BIT columns to TINYINT
P.S. Examining both aplication and MySQL logs allowed to narrow down the time span when something went wrong to about 2 minutes, but there were nothing abnormal in the logs in this period.
P.P.S. Application server is Glassfish 2.1.1, MySQL server version is 5.5.31-1~dotdeb and MySQL Connector/J version is 5.0.3.

Well, it turned out it was actually an issue with unclosed prepared statements.
When opened statements count at MySQL server reached its allowed maximum, application was still able to continue working somehow, withoout producing sql error:
Error Code: 1461 Can’t create more than max_prepared_stmt_count statements
But in that mode it started to wrap boolean values with quotes, causing all my troubles affecting BIT(1) columns.

MYSQL SELECT ... FOR UPDATE Not working?

I am having issues with MySQL's SELECT .. FOR UPDATE, here is the query I am trying to run:
SQL = "SELECT * " +
"FROM " + TableName + " " +
"WHERE out_status IN ("+outSStatus+") AND queued <= NOW() " +
"ORDER BY out_status, id_queue ASC "+ limitSql+
"FOR UPDATE";
After this, the thread will do an UPDATE and change the out_status to 99, which is then it should unlock the row.
I am running a multi-threaded java application, so 3 threads are running this SQL statement, but when thread 1 runs this, it doesn't lock (hide) its results from thread 2 & 3. Therefore threads 2 & 3 are getting the same results.
Also each thread is on its own mysql connection.
Can anybody please help me with this? OR perhaps have a better solution?
Much Appreciated.

You can use transactions

I had a similar issue. Both answers, from #Vikash and #Adeel Ansari, are valid suggestions. However, I solved the issue by using InnoDB engine instead of MyISAM. MyISAM only allows locking on table level, not on row level. You still need transactions, when using InnoDB.

It might be working, and you are unable to notice. Say thread 1 executed the statement, and committed the transaction automatically, because auto-commit was on. Then of course thread 2 would be able to run that too.
Try setting auto-commit off, using this method of Connection class and then see the result.