Voor de nieuwe release van Celerity CRM hebben we ook een nieuwe website gebouwd, u vindt de productinformatie vanaf nu op: www.celerity-crm.nl. Uiteraard is het daar ook mogelijk om een demo aan te vragen of een prijsindicatie voor uw organisatie te berekenen.
Just to keep others from searching for a “proper” way to handle this case: I just found out that Hibernate generates invalid SQL (at least in MySQL) when you pass an empty (not null) list to Restrictions.in(). The error occured in a simple query that tried to lookup a list of records by id. The code was something like this:
public List<Thing> findRecordsByIds(final List<Integer> ids) {
return (List<Thing>) getHibernateTemplate().execute(new HibernateCallback() {
public Object doInHibernate(Session session) throws HibernateException, SQLException {
return session.createCriteria(Thing.class).add(Restrictions.in("thingId", ids));
}
});
}
And it failed with a SQLGrammarException (which should never occur when using the Hibernate Query API). The Hibernate project knows about this as seen in their JIRA, but a fix is not yet delivered. Of course an easy fix to my example is:
public List<Thing> findRecordsByIds(final List<Integer> ids) {
if(ids.size() == 0) return Collections.emptyList();
return (List<Thing>) getHibernateTemplate().execute(new HibernateCallback() {
public Object doInHibernate(Session session) throws HibernateException, SQLException {
return session.createCriteria(Thing.class).add(Restrictions.in("thingId", ids));
}
});
}
Which also uses another function everybody should know about: Collections.emptyList() which in contrary to Collections.EMPTY_LIST uses a simple form of type inference to create a List<Thing> instead of a raw List and avoids a compiler warning.
