Hibernate error:Named query not known

The error message

Named query not known: my.simple.query
    [junit] org.hibernate.MappingException: Named query not known: relationship.delete_by_userId
    [junit]  at org.hibernate.impl.AbstractSessionImpl.getNamedQuery(AbstractSessionImpl.java:93)
    [junit]  at org.hibernate.impl.SessionImpl.getNamedQuery(SessionImpl.java:1287)

The context

You are using a named query in your application. Named queries are externalized and are coded in the hibernate mapping files rather than the application code

Possible reason(s) for this error

1) The name of the query in [...]