[hibernate-issues] [Hibernate-JIRA] Reopened: (HHH-2389) Improving DB2 dialect

Improving DB2 dialect --------------------- Key: HHH-2389 URL: http://opensource.atlassian.com/projects/hibernate/browse/HHH-2389 Project: Hibernate Core Issue Type: Improvement Components: query-hql Affects Versions: 3.2.1 Environment: Development based on v 3.2.1 Reporter: Nicolas Billard Assignee: Strong Liu Priority: Minor Fix For: 4.0.0.Beta1 Attachments: DB2Dialect.java The class joined to this issue overrides the DB2 dialect. The dialect included in hibernate doesn't work very well when you want to limit returned results (when you call setFirstResult and / or setMaxResults on a query) : - the instructions "fetch first XXX row only is not used - a temporary table is used when it's not usefull - when you have subselects, an exception can occur if subselects have order by clause (because of the getRowNumber method, not corrected here). This version of getLimitString() method generates faster requests (tests made on a table of 300000 rows shows that fetching rows from 20 to 30 takes 0.3 seconds with original version, 0.02 with this one).