如何比较在ICompositeUserType的NHibernate ICriteria查询中使用.NET类型？

Question

我有一个关于如何将传统CHAR数据库日期和时间字段合并为一个.NET DateTime属性在我的POCO here（谢谢Berryl！）如何结合回答StackOverflow问题。现在我正试图获得一个自定义的ICritera查询来对付那个非常有用的DateTime属性。这里是我的查询：

ICriteria criteria = 
    Session.CreateCriteria<InputFileLog>() 
    .Add(Expression.Gt(MembersOf<InputFileLog>.GetName(x => x.FileCreationDateTime), DateTime.Now.AddDays(-14))) 
    .AddOrder(Order.Desc(Projections.Id())) 
    .CreateCriteria(typeof(InputFile).Name) 
     .Add(Expression.Eq(MembersOf<InputFile>.GetName(x => x.Id), inputFileName)); 

IList<InputFileLog> list = criteria.List<InputFileLog>(); 

，这里是它生成查询：

SELECT this_.input_file_token as input1_9_2_, 
    this_.file_creation_date as file2_9_2_, 
    this_.file_creation_time as file3_9_2_, 
    this_.approval_ind as approval4_9_2_, 
    this_.file_id as file5_9_2_, 
    this_.process_name as process6_9_2_, 
    this_.process_status as process7_9_2_, 
    this_.input_file_name as input8_9_2_, 
    gonogo3_.input_file_token as input1_6_0_, 
    gonogo3_.go_nogo_ind as go2_6_0_, 
    inputfile1_.input_file_name as input1_3_1_, 
    inputfile1_.src_code as src2_3_1_, 
    inputfile1_.process_cat_code as process3_3_1_ 
FROM input_file_log this_ 
    left outer join go_nogo gonogo3_ on this_.input_file_token=gonogo3_.input_file_token 
    inner join input_file inputfile1_ on this_.input_file_name=inputfile1_.input_file_name 
WHERE this_.file_creation_date > :p0 and 
    this_.file_creation_time > :p1 and 
    inputfile1_.input_file_name = :p2 
ORDER BY this_.input_file_token desc; 
:p0 = '20100401', 
:p1 = '15:15:27', 
:p2 = 'LMCONV_JR' 

查询正是我所期望的，其实，除了它实际上并没有给我我想要的东西（所有在过去的2周内），因为在数据库中，它使用CHAR而不是DATE s进行比较。我不知道如何获得查询，以在查询中将CHAR值转换为DATE，而无需执行CreateSQLQuery（），，我想避免。有人知道怎么做吗？

更新： 我一直在寻找尝试使用Projections.SqlFunction()或公式来实现这一点，但目前为止无济于事。以下是我已经使用SqlFunction()的代码，但我得到一个错误NHibernate.QueryException : property does not map to a single column: FileCreationDateTime：

DateTime twoWeeksAgo = DateTime.Now.AddDays(-14); 
ICriteria criteria = 
    Session.CreateCriteria<InputFileLog>() 
    .Add(Restrictions.Gt(Projections.SqlFunction("to_date", NHibernateUtil.DateTime, Projections.Property(MembersOf<InputFileLog>.GetName(x => x.FileCreationDateTime))), twoWeeksAgo)) 
    //.Add(Expression.Gt(MembersOf<InputFileLog>.GetName(x => x.FileCreationDateTime), DateTime.Now.AddDays(-14))) 
    .AddOrder(Order.Desc(Projections.Id())) 
    .CreateCriteria(typeof(InputFile).Name) 
     .Add(Expression.Eq(MembersOf<InputFile>.GetName(x => x.Id), inputFileName)); 

我相信我在这里做得不对因为FileCreationDateTime使用自定义ICompositeUserType其拆分它不喜欢它仍然反正将.NET DateTime属性分成两个Oracle SQL CHAR列（有关详细信息，请参阅此StackOverflow question）。

Answer 1

我终于明白了这一点！下面的代码（出于某种原因StackOverflow的是使一些在这第一个代码的方法的名称片断类型的语法颜色）：

IList<InputFileLog> list = null; 
    DateTime twoWeeksAgo = DateTime.Now.AddDays(-14); 

    IProjection datePropProj = 
     DefaultStringFileCreationDateTimeType.GetFileCreationDateToDateSQLProjection(); 
    IProjection timePropProj = 
     DefaultStringFileCreationDateTimeType.GetFileCreationTimeToDateSQLProjection(); 

    IProjection dateConstProj = 
     DefaultStringFileCreationDateTimeType.GetFileCreationDateToDateSQLFunction(twoWeeksAgo); 
    IProjection timeConstProj = 
     DefaultStringFileCreationDateTimeType.GetFileCreationTimeToDateSQLFunction(twoWeeksAgo); 

    ICriteria criteria = 
     Session.CreateCriteria<InputFileLog>() 
     .Add(Restrictions.Or(Restrictions.GtProperty(datePropProj, dateConstProj), 
      Restrictions.And(Restrictions.EqProperty(datePropProj, dateConstProj), 
       Restrictions.GeProperty(timePropProj, timeConstProj)))) 
     .AddOrder(Order.Desc(Projections.Id())) 
     .CreateCriteria(typeof(InputFile).Name) 
      .Add(Expression.Eq(MembersOf<InputFile>.GetName(x => x.Id), inputFileName)); 

    list = criteria.List<InputFileLog>(); 

，这里是我用来创建SQLProjections和SQLFunctions方法。我把它们放在我用于FileCreationDateTime属性上的自定义类型映射的ICompositeUserType（DefaultStringFileCreationDateTime）中。

public class DefaultStringFileCreationDateTime : ICompositeUserType 
{ 
    . 
    . 
    . 
    public const string DotNetDateFormat = "yyyyMMdd"; 

    public const string DotNetTimeFormat = "HH:mm:ss"; 

    public const string DbDateFormat = "YYYYMMDD"; 

    public const string DbTimeFormat = "HH24:MI:SS"; 

    private const string _nullDateRepresentationInDb = "00000000"; 

    public struct DatabaseFieldNames 
    { 
     /// <summary> 
     /// File creation date column name. 
     /// </summary> 
     public const string FileCreationDate = "file_creation_date"; 

     /// <summary> 
     /// File creation time column name. 
     /// </summary> 
     public const string FileCreationTime = "file_creation_time"; 
    } 

    public static IProjection GetFileCreationDateToDateSQLProjection() 
    { 
     return ProjectionUtil.GetToDateSQLProjection(DatabaseFieldNames.FileCreationDate, DbDateFormat, NHibernateUtil.DateTime); 
    } 

    public static IProjection GetFileCreationTimeToDateSQLProjection() 
    { 
     return ProjectionUtil.GetToDateSQLProjection(DatabaseFieldNames.FileCreationTime, DbTimeFormat, NHibernateUtil.DateTime); 
    } 

    public static IProjection GetFileCreationDateToDateSQLFunction(DateTime dt) 
    { 
     return ProjectionUtil.GetToDateSQLFunction(dt, DotNetDateFormat, DbDateFormat); 
    } 

    public static IProjection GetFileCreationTimeToDateSQLFunction(DateTime dt) 
    { 
     return ProjectionUtil.GetToDateSQLFunction(dt, DotNetTimeFormat, DbTimeFormat); 
    } 
} 

我已经使用constsDatabaseFieldNamesstruct为PropertyNames成员实现，所以我能够重新用于Projections我需要以及这些硬编码列名。

这里的Projection实用工具类，其中通用to_date方式生活：

public class ProjectionUtil 
{ 
    public static IProjection GetToDateSQLProjection(
     string columnName, string dbToDateFormat, IType returnType) 
    { 
     return Projections.SqlProjection(
      string.Format("to_date({0}, '{1}') as {0}", columnName, dbToDateFormat), 
      new string[] { columnName }, 
      new IType[] { returnType }); 
    } 

    public static IProjection GetToDateSQLFunction(
     DateTime dt, string dotNetFormatString, string dbFormatString) 
    { 
     return Projections.SqlFunction(
      "to_date", 
      NHibernateUtil.DateTime, 
      Projections.Constant(dt.ToString(dotNetFormatString)), 
      Projections.Constant(dbFormatString)); 
    } 
} 

最后，下面是NHibernate的生成的Oracle SQL：

SELECT 
    this_.input_file_token as input1_9_2_, 
    this_.file_creation_date as file2_9_2_, 
    this_.file_creation_time as file3_9_2_, 
    this_.approval_ind as approval4_9_2_, 
    this_.file_id as file5_9_2_, 
    this_.process_name as process6_9_2_, 
    this_.process_status as process7_9_2_, 
    this_.input_file_name as input8_9_2_, 
    gonogo3_.input_file_token as input1_6_0_, 
    gonogo3_.go_nogo_ind as go2_6_0_, 
    inputfile1_.input_file_name as input1_3_1_, 
    inputfile1_.src_code as src2_3_1_, 
    inputfile1_.process_cat_code as process3_3_1_ 
FROM 
    input_file_log this_ 
    left outer join go_nogo gonogo3_ on this_.input_file_token=gonogo3_.input_file_token 
    inner join input_file inputfile1_ on this_.input_file_name=inputfile1_.input_file_name 
WHERE 
    (
     to_date(file_creation_date, 'YYYYMMDD') > to_date(:p0, :p1) or 
     (
      to_date(file_creation_date, 'YYYYMMDD') = to_date(:p2, :p3) and 
      to_date(file_creation_time, 'HH24:MI:SS') >= to_date(:p4, :p5) 
     ) 
    ) and 
    inputfile1_.input_file_name = :p6 
ORDER BY this_.input_file_token desc; 
:p0 = '20100415', 
:p1 = 'YYYYMMDD', 
:p2 = '20100415', 
:p3 = 'YYYYMMDD', 
:p4 = '18:48:48', 
:p5 = 'HH24:MI:SS', 
:p6 = 'LMCONV_JR' 

不能相信我有这个！我以为我不得不求助于ISQLQuery！