计数中的SQL投影与Nhibernate QueryOver不同

Question

我要在NHibernate QueryOver中生成以下查询。

SELECT E.EmployeeName
FROM   Employees E
   INNER JOIN Department D
           ON E.EmployeeId = E.EmployeeId
   INNER JOIN Qualifications Q
           ON E.EmployeeId = Q.EmployeeId
   WHERE D.DepartmentKey IN(1,2)
   AND Q.QualificationKey IN (3,4)
GROUP  BY EmployeeName
HAVING count(distinct STR(D.DepartmentKey) + STR(Q.QualificationKey)) = 2*2

我正在尝试应用具有SQL功能模板的Count Distinct的Having条件。

这是我对计数不同的代码： -

query.Where(Restrictions.Eq
(Projections.CountDistinct<Employee>(c => 
Projections.SqlFunction( new SQLFunctionTemplate (NHibernateUtil.String, 
"STR(?1) + STR(?2)"),
NHibernateUtil.String,
Projections.ProjectionList().
Add(Projections.Property(() => DepartmentAlias.DepartmentKey)).
Add(Projections.Property(() => QualificationAlias.QualificationKey)))),
departmentSelectionCount * qualificationSelectionCount))

我收到以下错误： -

{"Unrecognised method call in expression SqlFunction
(new SQLFunctionTemplate(NHibernateUtil.String, \"STR(?1) + STR(?2)\"),
NHibernateUtil.String, new [] {ProjectionList().
Add(Property(() => value(DepartmentAlias.DepartmentKey)).
Add(Property(() => value(QualificationAlias.QualificationKey))})"} 

对此有任何帮助将非常感谢!!

先谢谢!!