2012-07-02 209 views
4

我试图弄清楚这个问题相当长的时间。我有一个黑客的方式来使它工作。Fluent Nhibernate复合键映射

我只想知道这是否可能在流利NHibernate映射。

说我有例如两个表:

Table ComissionLevel 
{ 
    Year, 
    ComissionLevelID, 

    ... other properties .... 
} 
primary key (Year,ComissionLevelID) 

Table ClientCommission 
{ 
    Year, 
    ClientID, 
    CommissionLevelID_1, 
    CommissionLevelID_2, 

    ... other properties ... 
} 
primary key (Year,ClientID) 
foreign key CommissionLevel1 (Year,CommissionLevelID_1) 
foreign key CommissionLevel2 (Year,CommissionLevelID_2) 

目前我映射如下:现在

public ComissionLevelMap() 
{ 
    Schema("XXXX"); 
    Table("ComissionLevel"); 
    LazyLoad(); 
    CompositeId() 
    .KeyProperty(x => x.Year, set => { 
     set.ColumnName("Year"); 
     set.Access.Property(); }) 
    .KeyProperty(x => x.CommissionLevelID, set => { 
     set.ColumnName("CommissionLevelID"); 
     set.Length(10); 
     set.Access.Property(); }); 

    HasMany<ClientCommission>(x => x.ClientCommissions) 
    .Access.Property() 
    .AsSet() 
    .Cascade.AllDeleteOrphan() 
    .LazyLoad() 
    .Inverse() 
    .Generic() 
    .KeyColumns.Add("Year", mapping => mapping.Name("Year") 
                 .SqlType("NUMBER") 
                 .Nullable()) 
    .KeyColumns.Add("CommissionLevelID_1", mapping => mapping.Name("CommissionLevelID_1") 
                 .SqlType("VARCHAR2") 
                 .Nullable() 
                 .Length(10)); 
    HasMany<ClientCommission>(x => x.ClientCommission2s) 
    .Access.Property() 
    .AsSet() 
    .Cascade.AllDeleteOrphan() 
    .LazyLoad() 
    .Inverse() 
    .Generic() 
    .KeyColumns.Add("Year", mapping => mapping.Name("Year") 
                 .SqlType("NUMBER") 
                 .Nullable()) 
    .KeyColumns.Add("CommissionLevelID_2", mapping => mapping.Name("CommissionLevelID_2") 
                 .SqlType("VARCHAR2") 
                 .Nullable() 
                 .Length(10)); 
} 

public ClientCommissionMap() 
{ 
    Schema("XXXXX"); 
    Table("ClientCommission"); 
    LazyLoad(); 
    CompositeId() 
    .KeyProperty(x => x.ClientID, set => { 
     set.ColumnName("ClientID"); 
     set.Length(10); 
     set.Access.Property(); }) 
    .KeyProperty(x => x.Year, set => { 
     set.ColumnName("Year"); 
     set.Access.Property(); }); 
    References(x => x.ComissionLevel1) 
    .Class<ComissionLevel>() 
    .Access.Property() 
    .Cascade.None() 
    .LazyLoad() 
    .Insert() 
    .Update() 
    .Columns("Year", "CommissionLevelID_1"); 
    References(x => x.ComissionLevel2) 
    .Class<ComissionLevel>() 
    .Access.Property() 
    .Cascade.None() 
    .LazyLoad() 
    .Insert() 
    .Update() 
    .Columns("Year", "CommissionLevelID_2"); 

} 

我的问题是,每当我创建一个CommissionLevel并分配ClientCommission其收集,如果我通过call session.save(CommissionLevel)将它们保存起来,它会引起我的异常

<Index was out of range. Must be non-negative and less than the size of the collection. 
Parameter name: index>. 

这里我的问题是:

  1. NHibernate会自动保存关系吗?像:

    ClientCommission commission = new ClientCommission{Year = 2012, ClientID =SomeGuid}; 
        CommissionLevel newCommissionLevel = new CommissionLevel{Year = 2012, CommissionLevelID =NewCommissionLevelGuid}; 
    
        newCommissionLevel.ClientCommission1s.Add(commission); 
        newCommissionLevel.ClientCommission2s.Add(commission); 
    
        CommissionLevelRepo.Save(newCommissionLevel); 
    

    当我打电话CommissionLevelRepo.Save(newCommissionLevel),NHibernate的应该也会更新ClientCommission.ComissionLevel1而ClientCommission.ComissionLevel2

还是我不得不说

ClientCommission.ComissionLevel1 = newCommissionLevel; 
ClientCommission.ComissionLevel2 = newCommissionLevel; 
  1. 对于我得到的异常,这是因为NHibernate不会生成正确的列,它似乎会生成th ree年份专栏。因为如果我手动创建两个名为ComissionLevelID1和CommissionLevelID2的属性,请禁用ClientCommission上的.Insert()和.Update()它将正确保存它。

有人能告诉我映射这两个类的正确方法吗?

非常感谢。

+0

只是一个想法。如果你正在介绍所有这些复杂性。你可能做错了什么。简化您的映射和设计。你以后不会再维护它。 – DarthVader

回答

5

简短的回答:你不能对多重引用

份额列

长回答: NHibernate的对待每一个参考相互独立的,但的确消除了在插入语句重复列,因此引用尝试访问不再存在的列。它是这样做的,因为如果共享列在对象模型中的引用之间不同,它不能确定哪一个是正确的。

如果您可以更改数据库架构并使id具有唯一性,那么可以在ID和引用中全部忽略年份。

更新:

可以简化一些映射

CompositeId() 
    .KeyProperty(x => x.Year, set => { 
     set.ColumnName("Year"); 
     set.Access.Property(); }) 
    .KeyProperty(x => x.CommissionLevelID, set => { 
     set.ColumnName("CommissionLevelID"); 
     set.Length(10); 
     set.Access.Property(); }); 

// to 
CompositeId() 
    .KeyProperty(x => x.Year) // columnname is equal propertyname by default 
    .KeyProperty(x => x.CommissionLevelID, set => set.Length(10).Access.Property()); // property is default access and can also be left out 


.SqlType("VARCHAR2").Length(10) 
// to 
.Length(10) or .SqlType("VARCHAR2") 
// because length is ignored when sqltype is specified 
+0

非常感谢。不幸的是我不能改变db_schema。 DBA不允许我们这样做。我可以问你在哪里阅读了关于NHibernate的知识?有没有文档? – user1494907

+0

其中大部分是遗留数据库的痛苦经验。我通过Google搜索发现了原因,阅读了NH来源,试验和错误。每次遇到这样的问题,你都必须妥协。要么以不同的方式进行映射(例如,如果部分是唯一的,则忽略db中的主键/外键),将私有属性流入域模型,实现nhibernate挂钩以避开NHibernate的默认处理。 – Firo

0

对于组合键,看看Mapping Composite keys in Fluent NHibernate

为了简化映射,您可以更改主键只需一键,并创建一个独特的索引来表示它,但不是最好的解决方案。

之前(复合键):

CREATE TABLE XPTO (COD_XPTO1 INT NOT NULL IDENTITY, 
        COD_XPTO2 INT NOT NULL, 
        TXT_XPTO VARCHAR(10) NOT NULL) 
ALTER TABLE XPTO 
    ADD CONSTRAINT PK_XPTO (COD_XPTO1, COD_XPTO2) 

(具有唯一索引单个密钥)后:

CREATE TABLE XPTO (COD_XPTO1 INT NOT NULL IDENTITY, 
        COD_XPTO2 INT NOT NULL, 
        TXT_XPTO VARCHAR(10) NOT NULL) 

ALTER TABLE XPTO 
    ADD CONSTRAINT PK_XPTO (COD_XPTO1) 

CREATE UNIQUE INDEX UK_XPTO ON XPTO (COD_XPTO1, COD_XPTO2)