public partial class Share : Entity
    {
        /// <summary>
        /// Конструктор Паи
        /// </summary>
        /// <param name="id">уникальный идентификатор записи</param>
        public Share(Guid id)
            : base(id)
        {
        }

[Field]
        [Key]
        [Id("00000000-0000-0000-A0E2-AB84E1FC33A4")]
        public Guid Id { get; private set; }

        /// <summary>
        /// Фин. инструмент
        /// </summary>
        [Field(Nullable = false)]
        [Id("00000000-0000-0000-AD47-F3D0A397AA2E")]
        public FinTool FinTool { get; set; }

        /// <summary>
        /// Выражение для трансляции в SQL
        /// </summary>
        private static readonly Expression<Func<Share, string>> PduRegNumberExpression = e => e.FinTool == null ? null : Query.All<Fund>().FirstOrDefault(f => f.Person == e.FinTool.Emitter) != null ? Query.All<Fund>().FirstOrDefault(f => f.Person == e.FinTool.Emitter).PduRegNumber : null;

        /// <summary>
        /// Компилированное выражение для вызова в свойстве класса
        /// </summary>
        private static readonly Func<Share, string> PduRegNumberExpressionCompiled = PduRegNumberExpression.Compile();

/// <summary>
        /// Регистрационный номер правил ДУ
        /// Спр. Фондов поле Регистрационный номер правил ДУ
        /// </summary>
        [VirtualField]
        [Id("00000000-0000-0000-9F7C-99D0499814A2")]
        public string PduRegNumber
        {
            get { return PduRegNumberExpressionCompiled(this); }
        }

/// <summary>
        /// Класс-контейнер для связки вирт полей со свойствами класса
        /// </summary>
        [CompilerContainer(typeof(Expression))]
        public static class CustomLinqCompilerContainer
        {
            ///<summary>
            /// Связывает экспрешен с свойством класса
            ///</summary>
            ///<param name="assignmentExpression">Экспрешен для SQL</param>
            ///<returns>Результирующее выражение</returns>
            [Compiler(typeof(Share), "FinToolGroup", TargetKind.PropertyGet)]
            public static Expression ShareFinToolGroup(Expression assignmentExpression)
            {
                return finToolGroupExpression.BindParameters(assignmentExpression);
            }

            ///<summary>
            /// Связывает экспрешен с свойством класса
            ///</summary>
            ///<param name="assignmentExpression">Экспрешен для SQL</param>
            ///<returns>Результирующее выражение</returns>
            [Compiler(typeof(Share), "PduRegNumber", TargetKind.PropertyGet)]
            public static Expression SharePduRegNumber(Expression assignmentExpression)
            {
                return PduRegNumberExpression.BindParameters(assignmentExpression);
            }
        }
     }

[HierarchyRoot]
    [Id("3D4142E2-9A9E-43EE-0000-000000000000")]
    //[Index("Name", Unique = true, Name = "Person.IX_Name")]
    public partial class Person : Entity
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="T:Werp.Model.Models.Base.ReferenceBase"/> class.
        /// </summary>
        /// <param name="id">Идентификатор элемента</param>
        public Person(Guid id)
            : base(id)
        {
        }

/// <summary>
        /// Идентификатор
        /// Содержит уникальный Guid элемента.
        /// </summary>
        [Field]
        [Key]
        [Id("00000000-0000-0000-A0E2-AB84E1FC33A4")]
        public Guid Id { get; private set; }

        /// <summary>
        /// Идентификатор Int
        /// Идентификатор из мигрированных таблиц
        /// </summary>
        [Id("00000000-0000-0000-AB0C-1A2ABE603701")]
        [Field]
        public int IntId { get; set; }
}

[HierarchyRoot]
    [Id("8183DA48-F049-4157-0000-000000000000")]
    public class Fund : Entity
    {
        /// <summary>
        /// Initializes a new instance of the <see cref="T:Test.Model.Models.References.Fund"/> class.
        /// </summary>
        /// <param name="id">Идентификатор элемента</param>
        public Fund(Guid id)
            : base(id)
        {
        }

        [Field]
        [Key]
        [Id("00000000-0000-0000-A0E2-AB84E1FC33A4")]
        public Guid Id { get; private set; }

        /// <summary>
        /// Идентификатор Int
        /// Идентификатор из мигрированных таблиц
        /// </summary>
        [Id("00000000-0000-0000-AB0C-1A2ABE603701")]
        [Field]
        public int IntId { get; set; }

        /// <summary>
        /// Персона
        /// Ссылка на персону, которой назначена категория Фонд. Используется краткое наименование.
        /// </summary>
        [Field(Nullable = false)]
        [Id("00000000-0000-0000-A84B-6D0671F6BEFC")]
        public Person Person { get; set; }

        /// <summary>
        /// Рег.№ ПДУ
        /// Регистрационный номер правил ДУ
        /// </summary>
        [Field(Length = 50, Nullable = true)]
        [Id("00000000-0000-0000-8C0B-BA70B90B9CD6")]
        public string PduRegNumber { get; set; }

When I try to get list of Share, i get this SQL which is wrong

SELECT  [a].[Id] ,
        [a].[FinTool_Id] ,
        [a].[EmissionVolume] ,
        [a].[Version] ,
        [b].[#a.Name] ,
        [c].[#b.Id] ,
        [d].[#c.PduRegNumber]
FROM    ( SELECT TOP 41
                    [e].[Id] ,
                    191 AS [TypeId] ,
                    [e].[FinTool_Id] ,
                    [e].[EmissionVolume] ,
                    [e].[Version] ,
                    ROW_NUMBER() OVER ( ORDER BY [e].[Id] ASC ) AS [RowNumber0]
          FROM      [dbo].[Share] [e]
          WHERE     ( [e].[Version] < CAST('2010-07-15 00:00:00.000' AS DATETIME2) )
          ORDER BY  [e].[Id] ASC
        ) [a]
        INNER JOIN ( SELECT [f].[Id] AS [#a.Id] ,
                            146 AS [#a.TypeId] ,
                            [f].[IntId] AS [#a.IntId] ,
                            [f].[Emitter_Id] AS [#a.Emitter_Id] ,
                            [f].[FinToolGroup_Id] AS [#a.FinToolGroup_Id] ,
                            [f].[FinToolType_Id] AS [#a.FinToolType_Id] ,
                            [f].[Name] AS [#a.Name] ,
                            [f].[FullName] AS [#a.FullName] ,
                            [f].[Currency_Id] AS [#a.Currency_Id] ,
                            [f].[Nominal] AS [#a.Nominal] ,
                            [f].[Version] AS [#a.Version]
                     FROM   [dbo].[FinTool] [f]
                   ) [b] ON ( [a].[FinTool_Id] = [b].[#a.Id] )
        OUTER APPLY ( SELECT TOP 1
                                [g].[Id] AS [#b.Id]
                      FROM      [dbo].[Fund] [g]
                      WHERE     ( [g].[Person_Id] = [b].[#a.IntId] )
                      ORDER BY  [g].[Id] ASC
                    ) [c]
        OUTER APPLY ( SELECT TOP 1
                                [h].[Id] AS [#c.Id] ,
                                [h].[PduRegNumber] AS [#c.PduRegNumber]
                      FROM      [dbo].[Fund] [h]
                      WHERE     ( [h].[Person_Id] = [b].[#a.IntId] )
                      ORDER BY  [h].[Id] ASC
                    ) [d]
WHERE   ( [a].[RowNumber0] > 0 )
ORDER BY [a].[Id] ASC ,
        [b].[#a.Id] ASC ,
        [c].[#b.Id] ASC ,
        [d].[#c.Id] ASC ;

Msg 206, Level 16, State 2, Line 1 Operand type clash: uniqueidentifier is incompatible with int

This is because it tries to join INT and GUID fields like

WHERE     ( [h].[Person_Id] = [b].[#a.IntId] )

Updated at 09.08.2010 11:47:22

Guys?

Updated at 13.08.2010 15:31:32

as for 1) This code is executed not only in sql but also in out BL, where Person can be null thus leading into NullreferenceException. Moreover, it seems like you "optimize" this into smth like

( CASE WHEN ( CAST(1 AS BIT) <> 0 ) THEN @p0_1
                                                                  ELSE [c].[ActualizationDate]
                                                             END ) but this is wrong, when parameter goes null, so SQL server must generate new query plan

as for 2) Yes, this might be done

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