如何在HasMany中流畅地映射约束 [英] How to Fluently map with constraint in HasMany

问题描述

我是新手（流利）nHibernate。

我有3个表：

机构

•AgencyId（pk）

•AgencyAccountNo

AgencyAccount

•AgencyId（pk）（fk - > Agency。AgencyId）

•AgencyAccountNo pk）

•ChainId（fk - > AgencyChain.ChainId）

AgencyChain

•ChainId（pk）

AgencyAccount实际上是一个版本控制表。每当代理机构更改一个新的AgencyAccount行，并增加AgencyAccountNo。

我试图流利地映射Agency和AgencyChain中的关系，以便只返回Current AgencyAccount，但是遇到了很多麻烦。我尝试了很多很多东西，不能进入这里，似乎也找不到任何例子或文件。

您的方法是什么？

正常/简单way更新

 类AgencyMap：ClassMap< Agency> 
 {
 public AgencyMap（）
 {
 Id（a => a.Id）; 
 
地图（a => a.AccountNo）; 
} 
} 
 
 class AgencyAccountMap：ClassMap< AgencyAccount> 
 {
 public AgencyAccountMap（）
 {
 CompositeId（）
 .KeyReference（aa => aa.Agency，AgencyId）
 .KeyProperty （aa => aa.AccountNo，AgencyAccountNo）; 
 
参考文献（a => a.Chain）.Column（chainid）; 
} 
} 
 
 class AgencyChainMap：ClassMap< AgencyChain> 
 {
 public AgencyChainMap（）
 {
 Id（c => c.Id）; 
 
 
 HasMany（c => c.AgencyAccounts）
 .KeyColumn（chainid）
 //仅获得实际的AgencyAccounts 
。 Where（AgencyAccountNo =（SELECT a.AgencyAccountNo FROM Agency a WHERE a.AgencyId = AgencyId））; 
 
 //或者只对Agency有兴趣（使用Set来防止来自agencyaccounts历史的重复）
 HasManyToMany（c => c.Agencys）
 .Table （AgencyAccount）
 .ParentKeyColumn（chainid）
 .ChildKeyColumn（agencyid）
 .AsSet（）; 
 
 
 
 var account = session.Get< AgencyAccount>（new AgencyAccount {Agency = agency，AccountNo = agency.AccountNo}）; 
  

不使用Identity但是使用其他一些id代码的方式

  class AgencyMap：ClassMap< Agency> 
 {
 public AgencyMap（）
 {
表（AgencyAccount）; 
 Id（a => a.Id，AgencyId）。GeneratedBy.Sequence（agency_id_sequence）; //例如序列
 
其中（AgencyAccountNo =（SELECT a.AgencyAccountNo FROM Agency a WHERE a.AgencyId = AgencyId））; 
 
 
地图（a => a.AccountNo）; 
 
 Join（Agency，join => 
 {
 join.KeyColumn（AgencyId）; 
 join.Map（< some other prop> ）; 
} 
} 
} 
  

：

• 这使得为同一账户插入新的AgencyAccounts非常困难


• 显示AgencyAccounts的完整历史记录


• 可能存在许多微妙问题

I’m new to (fluent) nHibernate.
I have 3 tables:
Agency
• AgencyId (pk)
• AgencyAccountNo

AgencyAccount
• AgencyId (pk) (fk -> Agency. AgencyId)
• AgencyAccountNo (pk)
• ChainId (fk -> AgencyChain.ChainId)

AgencyChain
• ChainId (pk)

AgencyAccount is effectively a versioning table. Everytime an Agency changes a new AgencyAccount row with an incremented AgencyAccountNo.

I am trying to fluently map the relationships in Agency and AgencyChain so that only the Current AgencyAccount will be returned, but have had a lot of trouble. I have tried many, many things, too numerous to go into here, and can’t seem to find any examples or documentation on this.

What would your approach be?

解决方案

the normal/easy way Updated

class AgencyMap : ClassMap<Agency>
{
    public AgencyMap()
    {
        Id(a => a.Id);

        Map(a => a.AccountNo);
    }
}

class AgencyAccountMap : ClassMap<AgencyAccount>
{
    public AgencyAccountMap()
    {
        CompositeId()
            .KeyReference(aa => aa.Agency, "AgencyId")
            .KeyProperty(aa => aa.AccountNo, "AgencyAccountNo");

        References(a => a.Chain).Column("chainid");
    }
}

class AgencyChainMap : ClassMap<AgencyChain>
{
    public AgencyChainMap()
    {
        Id(c => c.Id);


        HasMany(c => c.AgencyAccounts)
            .KeyColumn("chainid")
            // to get only the actual AgencyAccounts
            .Where("AgencyAccountNo = (SELECT a.AgencyAccountNo FROM Agency a WHERE a.AgencyId = AgencyId)");

        // or if only interested in Agency (using a Set to prevent duplicates coming from the history of agencyaccounts)
        HasManyToMany(c => c.Agencys)
            .Table("AgencyAccount")
            .ParentKeyColumn("chainid")
            .ChildKeyColumn("agencyid")
            .AsSet();
    }
}

var account = session.Get<AgencyAccount>(new AgencyAccount { Agency = agency, AccountNo = agency.AccountNo });

the hackish way when not using Identity but some other id generation

class AgencyMap : ClassMap<Agency>
{
    public AgencyMap()
    {
        Table("AgencyAccount");
        Id(a => a.Id, "AgencyId").GeneratedBy.Sequence("agency_id_sequence"); // e.g. sequence

        Where("AgencyAccountNo = (SELECT a.AgencyAccountNo FROM Agency a WHERE a.AgencyId = AgencyId)");


        Map(a => a.AccountNo);

        Join("Agency", join =>
        {
            join.KeyColumn("AgencyId");
            join.Map(<some other prop>);
        }
    }
}

Note:

• this makes inserting new AgencyAccounts for the same Account very difficult
• cant show the complete history of AgencyAccounts
• possibly has a lot of subtle problems

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