Help me please:

I not understanding:

Unknown type '246 in column 0 of 1 in binary-encoded result




Hibernate version: 3.0

Mapping documents:


<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping>

<class name="iron.model.Banco" table="bancos">
<id name="id" column="idbancos" type="integer" unsaved-value="-1">
<generator class="native"/>
</id>

<property name="nombre" column="nombre" type="string"/>

</class>
</hibernate-mapping>




Code between sessionFactory.openSession() and session.close():

Session session = HibernateUtil.getSessionFactory().getCurrentSession();

session.beginTransaction();

System.out.println(session.createQuery("select sum(x.id) from Banco x").uniqueResult());

session.getTransaction().commit();




Full stack trace of any exception that occurs:

Exception in thread "main" org.hibernate.exception.GenericJDBCException: could not execute query
at org.hibernate.exception.SQLStateConverter.handledNonSpecificException(SQLStateConverter.java:103)
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:91)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:43)
at org.hibernate.loader.Loader.doList(Loader.java:2147)
at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2028)
at org.hibernate.loader.Loader.list(Loader.java:2023)
at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:393)
at org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:338)
at org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:172)
at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1121)
at org.hibernate.impl.QueryImpl.list(QueryImpl.java:79)
at org.hibernate.impl.AbstractQueryImpl.uniqueResult(AbstractQueryImpl.java:780)
at iron.bd.BD.prueba(BD.java:711)
at iron.bd.BD.main(BD.java:719)
Caused by: java.sql.SQLException: Unknown type '246 in column 0 of 1 in binary-encoded result set.
at com.mysql.jdbc.MysqlIO.extractNativeEncodedColumn(MysqlIO.java:3710)
at com.mysql.jdbc.MysqlIO.unpackBinaryResultSetRow(MysqlIO.java:3620)
at com.mysql.jdbc.MysqlIO.nextRow(MysqlIO.java:1282)
at com.mysql.jdbc.MysqlIO.readSingleRowSet(MysqlIO.java:2198)
at com.mysql.jdbc.MysqlIO.getResultSet(MysqlIO.java:413)
at com.mysql.jdbc.MysqlIO.readResultsForQueryOrUpdate(MysqlIO.java:1899)
at com.mysql.jdbc.MysqlIO.readAllResults(MysqlIO.java:1347)
at com.mysql.jdbc.ServerPreparedStatement.serverExecute(ServerPreparedStatement.java:1393)
at com.mysql.jdbc.ServerPreparedStatement.executeInternal(ServerPreparedStatement.java:958)
at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1705)
at org.hibernate.jdbc.AbstractBatcher.getResultSet(AbstractBatcher.java:186)
at org.hibernate.loader.Loader.getResultSet(Loader.java:1668)
at org.hibernate.loader.Loader.doQuery(Loader.java:662)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:224)
at org.hibernate.loader.Loader.doList(Loader.java:2144)
... 10 more



Name and version of the database you are using: Mysql 5.0

The generated SQL (show_sql=true):

Hibernate: select sum(banco0_.idbancos) as col_0_0_ from bancos banco0_