我有这个对象:
class Person { Int32 id; String name; /*..*/ Adress adress; }
class Employee : Person { String e_g_Tax; /*..*/ Guid relationshipToManagmentId; }
映射的以下前提:
(a) "relationsToManagmentId" 应该是外键.
(b) "关系到管理"表是一个非映射表,(应用程序的旧部分)
(c) 测绘战略是TPT。(至少对于新对象:-)
映射,直到现在:
public class PersonMap : ClassMap<Person> {
public PersonMap(){
Id(x => x.id);
Map (x => x.Nachname).Length(255).Not.Nullable();
/*..*/
References(x => x.Adresse).Class(typeof(Adresse)).Not.Nullable();
}
}
public class EmployeeMap : SubclassMap<Employee>
{
public EmployeeMap()
{
Map(x => x.e_g_Tax, "enjoytax")
.Not.Nullable();
/*..*/
Join("RelationshipToManagment", xJoin =>
{
//xJoin.Table("RelationshipToManagment");
xJoin.Fetch.Join();
xJoin.KeyColumn("ID");
xJoin.Map(x => x.relationshipToManagmentId)
.Not.Nullable() ;
}); // --> exception!!
我怎么写这个?
Join()
只能在主键(属性 ID)上联接到另一个表,但您需要联接在外键列上。普通引用可以满足您的需求
class Employee : Person
{
Management Management;
}
public EmployeeMap()
{
References(x => x.Management).Column("relationshipToManagmentId");
}
更新:如果您需要RelationshipToManagment
表中的只读信息,您可以使用公式属性
public EmployeeMap()
{
Map(x => x.RelationshipToManagment).Formula("(SELECT m.Title FROM RelationshipToManagment m WHERE m.Id = relationshipToManagmentId)");
}