Criteria doesn't support a chaining of 2 not restrictions (sql = not not criterion) ----------------------------------------------------------------------------------- Key: HHH-6643 URL: http://opensource.atlassian.com/projects/hibernate/browse/HHH-6643 Project: Hibernate Core Issue Type: Bug Components: query-criteria Affects Versions: 3.2.7 Environment: Oracle 10g Hibernate 3.2.7 Reporter: Lorber Sebastien Priority: Trivial When we do: "Restrictions.not( Restrictions.not( Restrictions.eq("field",3) ) );" Hibernate generates "where not not field=3" Which generates an SQL exception The correct SQL syntax is: "where not (not field=3)" (At least our Oracle) I think Hibernate should handle such a case. /!\ See org.hibernate.criterion.NotExpression#toSqlString It seems that for MySQLDialect the parenthesis are added, but not for other dialects... I don't know the sql specificities of all dialects but perhaps the parenthesis should be added also for oracle dialect? Note that we use a custom dialect, extending Oracle10gDialect For those interested: i'm doing two not on a criterion instead of using the criterion directly. In real world, my code sample would be a little more complex: sometimes we compose with a lot of criterions, in many different methods. So i do not exactly use Restrictions.not( Restrictions.not( criterion ) ); Trust me, bad luck, it happened that the dynamic composition of my restrictions, in one specific case, resulted on a double not restriction applied to a criterion. Note that an easy workaround of this is to "add the parenthesis manually". A conjunction is a bit like an "empty restriction" thus what i've done is: Restrictions.not( Restrictions.and( Restrictions.not( Restrictions.eq("field",3) ), Restrictions.conjunction() ) ); Adding the "not criterion" into conjunction containing only the criterion. This way, the sql of my inner not restriction become something like: ( not field = 3 AND 1=1 ) -> We can apply a not on that, while we weren't able on "not field = 3" -- This message is automatically generated by JIRA. For more information on JIRA, see: http://www.atlassian.com/software/jira