select new ... results in n+1 selects ------------------------------------- Key: HHH-544 URL: http://opensource.atlassian.com/projects/hibernate/browse/HHH-544 Project: Hibernate Core Issue Type: Improvement Components: core Affects Versions: 3.0.5 Environment: Hibernate 3.0.5, Oracle 8i, JDK 1.4.2 Reporter: Salvatore Insalaco Priority: Minor Using collection constructors in select clause of HQL (e.g. new map(...)) generates n + 1 SQL statements (one for primary keys, one for each object). This is a problem when there're clauses as "distinct" and "order by": select distinct o from MyEntity o order by o.description works, because in the generated SQL all the columns are mapped in the select clause; but: select distinct new map (o as result) from MyEntity o order by o.description doesn't work, because the first line of generated SQL is like: select distinct id from MyTable order by description and that's invalid sql (at least in Oracle): description shoud be placed in select clause.