Hibernate version:
I'm using standard jboss 4.04 ga: it says
11:55:52,108 INFO [Version] Hibernate EntityManager 3.2.0.CR1
11:55:52,139 INFO [Version] Hibernate Annotations 3.2.0.CR1
11:55:52,155 INFO [Environment] Hibernate 3.2 cr2

Full stack trace of any exception that occurs:

Name and version of the database you are using:
SQL server 2005

The generated SQL (show_sql=true): taken from exception
select distinct dataevento0_.codice as codice13_0_, postioccup1_.id_PostiOccupatiPerDataEvento as id1_33_1_, dataevento0_.codice_evento as codice14_13_0_, dataevento0_.provincia as provincia13_0_, dataevento0_.citta as citta13_0_, dataevento0_.nazione as nazione13_0_, dataevento0_.datainizio as datainizio13_0_, dataevento0_.orainizio as orainizio13_0_, dataevento0_.I_incidenza as I7_13_0_, dataevento0_.nominativo as nominativo13_0_, dataevento0_.id_ConfigurazioneLocale as id15_13_0_, dataevento0_.datainizioprevendita as datainiz9_13_0_, dataevento0_.I_imponibileintrattenimenti as I10_13_0_, dataevento0_.attivo as attivo13_0_, dataevento0_.I_tipotassazione as I12_13_0_, dataevento0_.stato as stato13_0_, postioccup1_.codice_data_evento as codice4_33_1_, postioccup1_.codice_titolo as codice5_33_1_, postioccup1_.id_BigliettoAbbonamento as id2_33_1_, postioccup1_.id_abbonamento as id6_33_1_, postioccup1_.id_ConfigurazioneLocale as id7_33_1_, postioccup1_.codice_ordine_posto as codice8_33_1_, postioccup1_.id_fila as id9_33_1_, postioccup1_.codice_posto as codice3_33_1_, postioccup1_.codice_data_evento as codice4_0__, postioccup1_.id_PostiOccupatiPerDataEvento as id1_0__ from DBServerFarm.DBS3.DataEvento dataevento0_ left outer join DBServerFarm.DBS3.PostiOccupatiPerDataEvento postioccup1_ on dataevento0_.codice=postioccup1_.codice_data_evento where dataevento0_.codice=?

Debug level Hibernate log excerpt:
12:06:45,233 INFO [LongType] could not read column value from result set: codice8_33_1_; The value supplied cannot be converted to BIGINT.
12:06:45,233 WARN [JDBCExceptionReporter] SQL Error: 0, SQLState: 22000
12:06:45,233 ERROR [JDBCExceptionReporter] The value supplied cannot be converted to BIGINT.
12:06:55,108 ERROR [STDERR] errore :javax.ejb.EJBTransactionRolledbackException: javax.persistence.PersistenceException: org.hibernate.exception.DataException: could not execute query

Let's start from the end... codice8_33_1_ is an alfanumeric varchar(2).... so no surprise it's not converted to BIGINT....

BUT!!!!

i checked the annotations.... the FK... it's correct!!!
DBServerFarm.DBS3.PostiOccupatiPerDataEvento.codice_ordine_posto
is connected to the right place... a varchar(2) PK from a very simple table... 2 columns: code, description
or i mean... it's in a 2 col FK....

id_ConfigurazioneLocale, codice_ordine_posto to OrdinePostoPerConfigurazioneLocali and there is a single col FK to OrdinePosto

so i really don't understand how hibernate try to convert to bigint...

As i write the mapping si quite complex.... i try to explain....

i have the table PostiOccupatiPerDataEvento with 7 (i mean SEVEN) columns with foreing keys.... plus a column with identity PK

id_ConfigurazioneLocale
codice_ordine_posto
id_fila
codice_data_evento
codice_titolo
id_BigliettoAbbonamento
id_abbonamento

codice_titolo, id_BigliettoAbbonamento, id_abbonamento are mutually exclusive... i mean 2 of these 3 must be null and the other must be a valid value.. they are similar entity...


id_ConfigurazioneLocale and codice_ordine_posto are FK for OrdinePostoPerConfigurazioneLocali ... but are also used for other FK :(

@ManyToOne(cascade={},
fetch=FetchType.LAZY)

@JoinColumns( {
@JoinColumn(name="id_ConfigurazioneLocale", unique=false, nullable=true, insertable=true, updatable=true),
@JoinColumn(name="codice_ordine_posto", unique=false, nullable=true, insertable=true, updatable=true) } )
public OrdinePostoPerConfigurazioneLocali getOrdinePostoPerConfigurazioneLocali() {
return this.ordinePostoPerConfigurazioneLocali;

}

id_ConfigurazioneLocale, codice_ordine_posto, id_fila, codice_data_evento are FK for FilePerOrdinePostoPerDataEvento

@ManyToOne(cascade={},
fetch=FetchType.LAZY)

@JoinColumns( {
@JoinColumn(name="id_ConfigurazioneLocale", unique=false, nullable=true, insertable=false, updatable=false),
@JoinColumn(name="codice_ordine_posto", unique=false, nullable=true, insertable=false, updatable=false),
@JoinColumn(name="id_fila", unique=false, nullable=true, insertable=false, updatable=false),
@JoinColumn(name="codice_data_evento", unique=false, nullable=true, insertable=false, updatable=false) } )
public FilePerOrdinePostoPerDataEvento getFilePerOrdinePostoPerDataEvento() {
return this.filePerOrdinePostoPerDataEvento;

}

codice_data_evento is the FK to DataEvento

@ManyToOne(cascade={},
fetch=FetchType.LAZY)

@JoinColumn(name="codice_data_evento", unique=false, nullable=true, insertable=false, updatable=false)
public DataEvento getDataEvento() {
return this.dataEvento;

}

i get this error with this simple EJbQuery:
String ejbQuery = "select distinct entity from DataEvento as entity "
+ "left outer join fetch entity.postiOccupatiPerDataEventos "
+ "where entity.codice = :codice ";

i checked the db data.... it's correct.. i try in sql manager.. and the query works.. i mean it fetch a dataEvento with the only postiOccupatiPerDataEvento present... but then hibernate try to convert to bigint an alfanumeric column!?!?!??!
Thanks in advice.....