public Long getEnvelopeTotal(AbstractEnvelope envelope) {
    String query = "select sum(t.amount) from User_Transaction t";
    Long result = (Long) hibernateUtil.getSession().createQuery(query).uniqueResult();
    return result;
}

@SomeMagicAnnotation(query="select sum(t.amount) from User_Transaction t")
private Long total;

@Entity(name = "Abstract_Envelope")
public abstract class AbstractEnvelope extends AbstractAccount {

    @OneToMany(mappedBy = "abstractEnvelope")
    private List<UserTransaction> userTransactions;
    private Long total;

    public List<UserTransaction> getUserTransactions() {
        return userTransactions;
    }

    public void setUserTransactions(List<UserTransaction> userTransactions) {
        this.userTransactions = userTransactions;
    }

    @Formula(value = "select sum(t.amount) from User_Transaction t")
    public Long getTotal() {
        return total;
    }

    public void setTotal(Long total) {
        this.total = total;
    }
}

@Entity(name = "User_Transaction")
@Inheritance(strategy = InheritanceType.JOINED)
public class UserTransaction extends AbstractPersistentObject {

    private String name;
    private Long amount;
    @Temporal(TemporalType.DATE)
    private Date transactionDate;
    private String checkNumber;
    private String note;
    @ManyToOne
    private SpendingAccount spendingAccount;
    @ManyToOne
    private AbstractEnvelope abstractEnvelope;
    @OneToMany(mappedBy = "parentTransaction")
    private List<SplitTransaction> splitTransactions;

    public AbstractEnvelope getAbstractEnvelope() {
        return abstractEnvelope;
    }

    public void setAbstractEnvelope(AbstractEnvelope abstractEnvelope) {
        this.abstractEnvelope = abstractEnvelope;
    }

    public Long getAmount() {
        return amount;
    }

    public void setAmount(Long amount) {
        this.amount = amount;
    }

    public String getCheckNumber() {
        return checkNumber;
    }

    public void setCheckNumber(String checkNumber) {
        this.checkNumber = checkNumber;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getNote() {
        return note;
    }

    public void setNote(String note) {
        this.note = note;
    }

    public Date getTransactionDate() {
        return transactionDate;
    }

    public void setTransactionDate(Date transactionDate) {
        this.transactionDate = transactionDate;
    }

    public SpendingAccount getSpendingAccount() {
        return spendingAccount;
    }

    public void setSpendingAccount(SpendingAccount spendingAccount) {
        this.spendingAccount = spendingAccount;
    }
}

Hibernate: select this_.id as id0_6_, this_.version as version0_6_, this_.applicationInstance_id as applicat2_9_6_, this_.name as name9_6_, select sum(t.amount) from User_Transaction t where t.abstractenvelope_id = this_.id as formula0_6_, this_.clazz_ as clazz_6_, applicatio2_.id as id0_0_, applicatio2_.version as version0_0_, applicatio2_.accountTransfersEnvelope_id as accountT1_2_0_, applicatio2_.creditCardPaymentsEnvelope_id as creditCa2_2_0_, applicatio2_.endUser_id as endUser3_2_0_, applicatio2_.incomeCashPoolEnvelope_id as incomeCa4_2_0_, applicatio2_.newTransactionsEnvelope_id as newTrans5_2_0_, accounttra3_.id as id0_1_, accounttra3_.version as version0_1_, select sum(t.amount) from User_Transaction t where t.abstractenvelope_id = accounttra3_.id as formula0_1_, creditcard4_.id as id0_2_, creditcard4_.version as version0_2_, select sum(t.amount) from User_Transaction t where t.abstractenvelope_id = creditcard4_.id as formula0_2_, enduser5_.id as id0_3_, enduser5_.version as version0_3_, enduser5_.email as email1_3_, enduser5_.password as password1_3_, incomecash6_.id as id0_4_, incomecash6_.version as version0_4_, select sum(t.amount) from User_Transaction t where t.abstractenvelope_id = incomecash6_.id as formula0_4_, newtransac7_.id as id0_5_, newtransac7_.version as version0_5_, select sum(t.amount) from User_Transaction t where t.abstractenvelope_id = newtransac7_.id as formula0_5_ from ( select id, nullif('x','x') as applicationInstance_id, nullif('x','x') as name, version, 5 as clazz_ from New_Transactions_Envelope union all select id, nullif('x','x') as applicationInstance_id, nullif('x','x') as name, version, 6 as clazz_ from Account_Transfers_Envelope union all select id, nullif('x','x') as applicationInstance_id, nullif('x','x') as name, version, 7 as clazz_ from Income_Cash_Pool union all select id, nullif('x','x') as applicationInstance_id, nullif('x','x') as name, version, 8 as clazz_ from Credit_Card_Payments_Envelope union all select id, applicationInstance_id, name, version, 9 as clazz_ from User_Envelope ) this_ left outer join Application_Instance applicatio2_ on this_.applicationInstance_id=applicatio2_.id left outer join Account_Transfers_Envelope accounttra3_ on applicatio2_.accountTransfersEnvelope_id=accounttra3_.id left outer join Credit_Card_Payments_Envelope creditcard4_ on applicatio2_.creditCardPaymentsEnvelope_id=creditcard4_.id left outer join End_User enduser5_ on applicatio2_.endUser_id=enduser5_.id left outer join Income_Cash_Pool incomecash6_ on applicatio2_.incomeCashPoolEnvelope_id=incomecash6_.id left outer join New_Transactions_Envelope newtransac7_ on applicatio2_.newTransactionsEnvelope_id=newtransac7_.id

getEnvelopeTotal
Hibernate:
    select
        this_.id as id2_6_,
        this_.version as version2_6_,
        this_.applicationInstance_id as applicat5_2_6_,
        this_.name as name2_6_,
        select
            sum(t.amount)
        from
            User_Transaction t
        where
            t.abstractenvelope_id = this_.id as formula0_6_, this_.DTYPE as DTYPE2_6_, applicatio2_.id as id1_0_, applicatio2_.version as version1_0_, applicatio2_.accountTransfersEnvelope_id as accountT3_1_0_, applicatio2_.creditCardPaymentsEnvelope_id as creditCa4_1_0_, applicatio2_.endUser_id as endUser5_1_0_, applicatio2_.incomeCashPoolEnvelope_id as incomeCa6_1_0_, applicatio2_.newTransactionsEnvelope_id as newTrans7_1_0_, accounttra3_.id as id2_1_, accounttra3_.version as version2_1_, select
                sum(t.amount)
            from
                User_Transaction t
            where
                t.abstractenvelope_id = accounttra3_.id as formula0_1_, creditcard4_.id as id2_2_, creditcard4_.version as version2_2_, select
                    sum(t.amount)
                from
                    User_Transaction t
                where
                    t.abstractenvelope_id = creditcard4_.id as formula0_2_, enduser5_.id as id0_3_, enduser5_.version as version0_3_, enduser5_.email as email0_3_, enduser5_.password as password0_3_, incomecash6_.id as id2_4_, incomecash6_.version as version2_4_, select
                        sum(t.amount)
                    from
                        User_Transaction t
                    where
                        t.abstractenvelope_id = incomecash6_.id as formula0_4_, newtransac7_.id as id2_5_, newtransac7_.version as version2_5_, select
                            sum(t.amount)
                        from
                            User_Transaction t
                        where
                            t.abstractenvelope_id = newtransac7_.id as formula0_5_
                        from
                            Abstract_Envelope this_
                        left outer join
                            Application_Instance applicatio2_
                                on this_.applicationInstance_id=applicatio2_.id
                        left outer join
                            Abstract_Envelope accounttra3_
                                on applicatio2_.accountTransfersEnvelope_id=accounttra3_.id
                        left outer join
                            Abstract_Envelope creditcard4_
                                on applicatio2_.creditCardPaymentsEnvelope_id=creditcard4_.id
                        left outer join
                            End_User enduser5_
                                on applicatio2_.endUser_id=enduser5_.id
                        left outer join
                            Abstract_Envelope incomecash6_
                                on applicatio2_.incomeCashPoolEnvelope_id=incomecash6_.id
                        left outer join
                            Abstract_Envelope newtransac7_
                                on applicatio2_.newTransactionsEnvelope_id=newtransac7_.id
[2009-07-10 14:33:10,317] WARN     0[main] - org.hibernate.util.JDBCExceptionReporter.logExceptions(JDBCExceptionReporter.java:77) - SQL Error: 1064, SQLState: 42000
[2009-07-10 14:33:10,320]ERROR     3[main] - org.hibernate.util.JDBCExceptionReporter.logExceptions(JDBCExceptionReporter.java:78) - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'select sum(t.amount) from User_Transaction t where t.abstractenvelope_id = this_' at line 1

@Formula(value = "(select sum(t.amount) from User_Transaction t)")