当我运行linq查询时,它试图将SchoolInfo.SchoolInfoId映射到SchoolId.SchoolId。
如何定义正确的映射,以便它知道将SchoolInfo.SchoolId映射到School.SchoolId?
这是代码优先。
SQL 表
table School
(
int SchoolId not null PK
)
table SchoolInfo
(
int SchoolInfoId not null PK
int SchoolId not null FK
)
模型
class School
{
[Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
int schoolId;
virtual SchoolInfo SchoolInfo;
}
class SchoolInfo
{
[Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
int schoolInfoId;
int schoolId;
virtual School School
}
modelBuilder.Entity<School>().HasOptional(a => a.SchoolInfo).WithRequired(a => a.School);
更合适的方法是:
数据库:
TABLE School (
INT SchoolId NOT NULL PK
)
TABLE SchoolInfo (
INT SchoolId NOT NULL PK -- FK
)
学校模式:
public class School
{
[Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
public int schoolId { get; set; }
public virtual SchoolInfo SchoolInfo { get; set; }
}
学校信息模型选项 1:
public class SchoolInfo
{
[Key, ForeignKey("School")]
public int schoolId { get; set; }
public virtual School School { get; set; }
}
学校信息模型选项 2:
public class SchoolInfo
{
[ForeignKey("School")]
public int SchoolInfoId { get; set; }
public virtual School School { get; set; }
}
学校信息模型选项 3:
public class SchoolInfo
{
[Key]
public int schoolId { get; set; }
public virtual School School { get; set; }
}
// Relationship:
modelBuilder.Entity<School>().HasOptional(a => a.SchoolInfo).WithRequired(a => a.School);
由于您提到的限制,另一种方法是:
您的实际数据库:
TABLE School (
INT SchoolId NOT NULL PK
)
TABLE SchoolInfo (
INT SchoolInfoId NULL PK
INT SchoolId NOT NULL FK -- WITH UNIQUE CONSTRAINT TO ENSUERE ONE TO ONE
)
学校模式:
public class School
{
[Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
public int schoolId { get; set; }
public virtual SchoolInfo SchoolInfo { get; set; }
}
学校信息模型选项 1:
public class SchoolInfo
{
public int schoolInfoId { get; set; }
[Key]
public int schoolId { get; set; }
public virtual School School { get; set; }
}
// Relationship:
modelBuilder.Entity<School>().HasOptional(a => a.SchoolInfo).WithRequired(a => a.School);
学校信息模型选项 2(我没有测试它):
public class SchoolInfo
{
[Key, DatabaseGenerated(DatabaseGeneratedOption.Identity)]
public int schoolInfoId { get; set; }
[ForeignKey("School")]
public int schoolId { get; set; }
public virtual School School { get; set; }
}
// Relationship:
modelBuilder.Entity<School>().HasOptional(a => a.SchoolInfo).WithRequired(a => a.School);
你可以看到:
http://www.entityframeworktutorial.net/entity-relationships.aspxhttp://www.entityframeworktutorial.net/code-first/configure-one-to-one-relationship-in-code-first.aspx