我使用 S#arpLite 开发了一个 webapp 来构建一个查询,从许多表中获取一个列表。 使用 NHibernate 版本 3.3.1.4000
我在应用程序运行时遇到错误,例如
`NHibernate System.NotSupportedException Specified method is not supported. {Name = "PolymorphicQuerySourceDetector" FullName = "NHibernate.Hql.Ast.ANTLR.PolymorphicQuerySourceDetector"} at NHibernate.Hql.Ast.ANTLR.PolymorphicQuerySourceDetector.GetClassName(IASTNode querySource) at NHibernate.Hql.Ast.ANTLR.PolymorphicQuerySourceDetector.Process(IASTNode tree) at NHibernate.Hql.Ast.ANTLR.AstPolymorphicProcessor.Process() at NHibernate.Hql.Ast.ANTLR.AstPolymorphicProcessor.Process(IASTNode ast, ISessionFactoryImplementor factory) at NHibernate.Hql.Ast.ANTLR.ASTQueryTranslatorFactory.CreateQueryTranslators(IASTNode ast, String queryIdentifier, String collectionRole, Boolean shallow, IDictionary`2 filters, ISessionFactoryImplementor factory) at NHibernate.Hql.Ast.ANTLR.ASTQueryTranslatorFactory.CreateQueryTranslators(String queryIdentifier, IQueryExpression queryExpression, String collectionRole, Boolean shallow, IDictionary`2 filters, ISessionFactoryImplementor factory) at NHibernate.Engine.Query.HQLExpressionQueryPlan.CreateTranslators(String expressionStr, IQueryExpression queryExpression, String collectionRole, Boolean shallow, IDictionary`2 enabledFilters, ISessionFactoryImplementor factory) at NHibernate.Engine.Query.HQLExpressionQueryPlan..ctor(String expressionStr, IQueryExpression queryExpression, String collectionRole, Boolean shallow, IDictionary`2 enabledFilters, ISessionFactoryImplementor factory) at NHibernate.Engine.Query.HQLExpressionQueryPlan..ctor(String expressionStr, IQueryExpression queryExpression, Boolean shallow, IDictionary`2 enabledFilters, ISessionFactoryImplementor factory) at NHibernate.Engine.Query.QueryPlanCache.GetHQLQueryPlan(IQueryExpression queryExpression, Boolean shallow, IDictionary`2 enabledFilters) at NHibernate.Impl.AbstractSessionImpl.GetHQLQueryPlan(IQueryExpression queryExpression, Boolean shallow) at NHibernate.Impl.AbstractSessionImpl.CreateQuery(IQueryExpression queryExpression) at NHibernate.Linq.DefaultQueryProvider.PrepareQuery(Expression expression, IQuery& query, NhLinqExpression& nhQuery) at NHibernate.Linq.DefaultQueryProvider.Execute(Expression expression) at NHibernate.Linq.DefaultQueryProvider.Execute[TResult](Expression expression) at Remotion.Linq.QueryableBase`1.GetEnumerator() at System.Collections.Generic.List`1..ctor(IEnumerable`1 collection) at System.Linq.Enumerable.ToList[TSource](IEnumerable`1 source) at EzLife.Tasks.EmployeeCudTasks.GetEmployees(List`1 listSkill, List`1 listDepartment, List`1 listAssignment, String searchTerm, String jobtitle, String tier, String competency, Nullable`1 startDate, Nullable`1 endDate, Int32 effort, Nullable`1 active, Int32 currentPage, Int32 pageSize, Int32 sortId, Int32 sortName, Int32 sortTitle, Int32 sortTier, Int32 sortJoinedDate, Int32 sortDepartment) in d:\Projects\EzLife\_source\Ezlife\app\EzLife.Tasks\EmployeeCudTasks.cs:line 206`
这是我的代码
`public static IQueryable GetEmployeesQ(this IQueryable employees, IQueryable employeeTitles, int currentPage,int pageSize) { var query = from employee in employees join employeeTitle in employeeTitles on employee.Id equals employeeTitle.Employee.Id select new EmployeeDto() { Id = employee.Id, CustomCode = employee.CustomCode, FirstName = employee.FirstName, LastName = employee.LastName, MiddleName = employee.MiddleName, FullName = string.Empty, JoinedDate = employee.JoinedDate, }; return query; }public static IQueryable GetEmployeeTitlesQ(this IQueryable employeeTitles) { return from et1 in employeeTitles join et2 in ( from et in employeeTitles orderby et.Employee.Id, et.StartDate group et by et.Employee.Id into etmax select new { Id = etmax.Max(et => et.Id) } ) on et1.Id equals et2.Id select et1; }`
I call GetEmployeeTitlesQ in GetEmployeesQ as : ' public IList GetEmployees(int currentPage = 1, int pageSize = 20) {
IList<EmployeeDto> employees = new List<EmployeeDto>(); IQueryable<EmployeeTitle> employeeTitles = employeeTitleRep.GetAll().GetEmployeeTitlesQ(); IQueryable<EmployeeDto> employeeDto = employeeRep.GetAll().GetEmployeesQ( employeeTitles , jobTitles , currentPage , pageSize); try { employees = employeeDto.ToList(); } catch (Exception ex) { var mess = ex.Message.ToString(); } return employees; }
' 我猜 Max() 函数有问题,但我不知道为什么。 有什么办法可以解决它吗?
最佳答案
NHibernate 无法将每个 LINQ 查询转换为 SQL。对我来说,重新排列 where
和 join
语句的顺序就足够了。
关于c# - NHibernate 不支持指定的方法,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/32835670/