如何在NHompnate ICriteria查询中使用.NET类型来比较ICompositeUserType？

Question

我有一个解答的StackOverflow问题，关于如何将遗留CHAR数据库日期和时间字段合并到我的POCO中的一个.NET DateTime属性中 here（非常感谢Berryl！）。现在我试图获得一个自定义的ICritera查询来对付那个非常DateTime的属性无济于事。这是我的疑问：

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>();

以下是它产生的查询：

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，实际上，除了它实际上并没有给我我想要的东西（过去2周内的所有行），因为在DB中它比使用{{1}进行比较更大而不是CHAR s。我不知道如何在查询中将DATE值转换为CHAR而不执行CreateSQLQuery（），我想避免。有谁知道怎么做？

更新： 我一直在努力尝试使用DATE或公式来实现这一目标，但到目前为止无济于事。这是我使用Projections.SqlFunction()的代码，但我收到SqlFunction()错误：

NHibernate.QueryException : property does not map to a single column: FileCreationDateTime

我确定我在这里做错了但它仍然不喜欢它因为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)); 使用自定义FileCreationDateTime将.NET ICompositeUserType属性拆分为两个Oracle SQL DateTime列（有关详细信息，请参阅此StackOverflow question。）

Answer 1

我终于搞清楚了！这里是代码（由于某种原因，StackOverflow在第一个代码片段中将一些方法名称作为类型的语法颜色）：

    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>();

这是我用来创建SQLProjections和SQLFunctions的方法。我将它们放在ICompositeUserType（DefaultStringFileCreationDateTime）中，用于FileCreationDateTime属性上的自定义类型映射。

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);
    }
}

我已经将consts DatabaseFieldNames struct用于PropertyNames成员实现，因此我能够为{{1}重用这些硬编码列名称我也需要。

以下是通用Projections方法所在的Projection实用程序类：

to_date

最后，这是NHibernate生成的Oracle SQL：

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));
    }
}

简直不敢相信我得到了这个！我以为我肯定不得不求助于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' ！