流利的NHibernate映射-执行时列名称错误

时间:2018-12-04 23:29:57

标签: c# nhibernate fluent-nhibernate

我是Fluent NHibernate的新手,我不得不请您提供一些帮助。 我的简单数据库(SQL Server 2017,数据库优先方法)脚本:

CREATE TABLE [dbo].[CDs](
    [IdCD] [int] IDENTITY(1,1) NOT NULL,
    [Artist] [nvarchar](255) NOT NULL,
    [Title] [nvarchar](255) NOT NULL,
    [Tracks] [nvarchar](255) NOT NULL,
    [Box] [nvarchar](255) NOT NULL,
    [Producer] [int] NOT NULL,
    [Year] [int] NOT NULL,
    [Extras] [nvarchar](255) NOT NULL,
    [CreationDate] [datetime2](7) NOT NULL,
 CONSTRAINT [PK__CDs__B77390873411F1EA] PRIMARY KEY CLUSTERED 
(
    [IdCD] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]

CREATE TABLE [dbo].[Producers](
    [IdProducer] [int] IDENTITY(1,1) NOT NULL,
    [Name] [nvarchar](100) NOT NULL,
 CONSTRAINT [PK_Producers2] PRIMARY KEY CLUSTERED 
(
    [IdProducer] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]

表之间是一对多关系。表“ CD”中的“ Producer”列为FK,“ Producers”表中的“ IdProducer”为PK,它是父级。需要明确的是-一个“生产者”可以有许多“ CD”。 因此,我根据网络上阅读的许多文章为这2个表创建了模型类:

    public class CDsModel
    {
        public virtual int IdCD { get; set; }
        public virtual string Artist { get; set; }
        public virtual string Title { get; set; }
        public virtual string Tracks { get; set; }
        public virtual string Box { get; set; }
        public virtual int Producer { get; set; }
        public virtual int Year { get; set; }
        public virtual string Extras { get; set; }
        public virtual DateTime CreationDate { get; set; }
        public virtual ProducersModel Producers { get; set; }
    }

    public class ProducersModel
    {
        public virtual int IdProducer { get; set; }
        public virtual string Name { get; set; }
        public virtual IList<CDsModel> CDs { get; set; }
    }

接下来,我创建了映射:

public CDsMap()
        {
            Table("CDs");

            Id(x => x.IdCD, "IdCD").GeneratedBy.Identity().UnsavedValue(0);

            Map(x => x.Artist);
            Map(x => x.Title);
            Map(x => x.Tracks);
            Map(x => x.Box);
            Map(x => x.Producer);
            Map(x => x.Year);
            Map(x => x.Extras);
            Map(x => x.CreationDate);
            References(x => x.Producers, "IdProducer");
        }

 public ProducersMap()
        {
            Table("Producers");

            Id(x => x.IdProducer, "IdProducer").GeneratedBy.Identity().UnsavedValue(0);

            Map(x => x.Name);

            HasMany(x => x.CDs).KeyColumn("Producer").AsBag().Not.LazyLoad().Inverse().Cascade.AllDeleteOrphan();
        }

在调用控制器方法时,将以以下方式创建会话:

    _sessionFactory = Fluently.Configure()
        .Database(MsSqlConfiguration.MsSql2012.ConnectionString(ConnectionString).ShowSql)
        .Mappings(m => m.FluentMappings.AddFromAssemblyOf<ProducersModel>())
        .ExposeConfiguration(cfg => new SchemaExport(cfg).Create(false, false))
        .BuildSessionFactory();

出现我的问题-例外:

NHibernate.Exceptions.GenericADOException: 'could not initialize a collection: [NHApi.Models.ProducersModel.CDs#3][SQL: SELECT cds0_.Producer as producer6_0_1_, cds0_.IdCD as idcd1_0_1_, cds0_.IdCD as idcd1_0_0_, cds0_.Artist as artist2_0_0_, cds0_.Title as title3_0_0_, cds0_.Tracks as tracks4_0_0_, cds0_.Box as box5_0_0_, cds0_.Producer as producer6_0_0_, cds0_.Year as year7_0_0_, cds0_.Extras as extras8_0_0_, cds0_.CreationDate as creationdate9_0_0_, cds0_.IdProducer as idproducer10_0_0_ FROM CDs cds0_ WHERE cds0_.Producer=?]'

Inner Exception
SqlException: Wrong column name IdProducer

我试图在模型,映射和数据库中操纵列名,但是没有运气。 对于此问题的任何帮助将不胜感激。

1 个答案:

答案 0 :(得分:1)

更多挖掘和回答非常简单... 我发现了这篇文章:Fluent NHibernate Many to one mapping

首先,我在CDsMap中的对象引用中做错了。是:

References(x => x.Producers, "IdProducer");

它应该是:

References(x => x.Producers, "Producer");

因为引用应该导致表的FK字段。

接下来的事情是我的ProducersModel中没有构造函数和List对象init,因此我添加了以下构造函数:

public ProducersModel()
{
    CDs = new List<CDsModel>();
}

但是我仍然对重复的字段“生产者”有一个例外。最后一步是从CDsModel和CDsMap中删除“生产者”字段。