I have a child entity:
public class PhoneNumber : KeyedEntityBase
{
public string Number { get; set; }
public string Extension { get; set; }
}
that exists in multiple parents:
public class Customer : KeyedEntityBase
{
public string Name { get; set; }
public PhoneNumber PhoneNumber { get; set; }
}
public class Vendor : KeyedEntityBase
{
public string VendorName { get; set; }
public PhoneNumber PhoneNumber { get; set; }
}
When I want to delete a PhoneNumber from one of the parents I just null it out. Is there a way I can make Entity Framework handle deleting orphan PhoneNumber instances when using a Repository pattern? I believe NHibernate's all-delete-orphan cascade mode does this. Now to do this I have to create a PhoneNumberRepository and explicitly delete the PhoneNumber after I null it out on the parent, and this smells.
Related
I have the following main class:
public class ResearchOutcome
{
public ResearchOutcomeCategory ResearchOutcomeCategory { get; set; }
public string? UniqueIdentifier { get; set; }
}
And the category class is:
public class ResearchOutcomeCategory
{
public int Id { get; set; }
public string Name { get; set; }
public string? Description { get; set; }
}
The View models for above classes are:
public class ResearchOutcomeDetailVm : IMapFrom<ResearchOutcome>
{
public int Id { get; set; }
public virtual ResearchOutcomeCategoryDetailVm ResearchOutcomeCategory { get; set; }
}
public class ResearchOutcomeCategoryDetailVm : IMapFrom<ResearchOutcomeCategory>
{
public int Id { get; set; }
public string Name { get; set; }
public string Description { get; set; }
}
Now, I have used the following mapping profile:
// First this one
profile.CreateMap<ResearchOutcomeCategory, ResearchOutcomeCategoryDetailVm>();
profile.CreateMap<ResearchOutcome, ResearchOutcomeDetailVm>();
//Then I tried this one
profile.CreateMap<ResearchOutcome, ResearchOutcomeDetailVm>()
.ForMember(o => o.ResearchOutcomeCategory,
cat => cat.MapFrom( o => o.ResearchOutcomeCategory));
But the ResearchOutcomeCategory is always null. Any help would be appreciated.
After digging more, I identified that I was not "Including" the relevant item in the query, hence, the view model was always empty. Pretty dumb on my part :D
Regarding the mapping, if the properties (even complex ones) have the same names, then the mapper will map them automatically. So simply this line worked
profile.CreateMap<ResearchOutcomeCategory, ResearchOutcomeCategoryDetailVm>();
Hope it helps someone
I am trying to implement DbContext for couple of tables called 'Employee' and 'Department'
Relationship between Employee and Department is many to one. i.e. department can have many employees.
Below are the EntityFramework classes I designed ( CodeFirst approach )
[Table("Employee")]
public class Employee
{
[DatabaseGenerated(System.ComponentModel.DataAnnotations.Schema.DatabaseGeneratedOption.Identity)]
public int Id { get; set; }
[Column("Name")]
public string Name { get; set; }
[Column("Department_ID")]
public int Department_ID { get; set; }
public virtual Department Department { get; set; }
}
[Table("Department")]
public class Department
{
[DatabaseGenerated(DatabaseGeneratedOption.Identity)]
public int ID { get; set; }
[Column("Name")]
public string Name { get; set; }
public virtual ICollection<Employee> Employees { get; set; }
}
While adding Employee record I am getting below exception
"Invalid column name 'Department_ID1'."
I am not sure why EF is referring to Department_ID1. Do I need to add configuration in OnModelCreating method of DbContext?
I am using EF version 6.1.1
I've also gotten this problem in my EF one-many deals where the one has a List of the many property and my mapping didn't specify that property. For example take:
public class Notification
{
public long ID { get; set; }
public IList<NotificationRecipient> Recipients { get; set; }
}
then
public class NotificationRecipient
{
public long ID { get; set; }
public long NotificationID { get; set; }
public Notification Notification { get; set; }
}
Then in my mapping, the way that caused the Exception (the incorrect way):
builder.HasOne(x => x.Notification).WithMany()
.HasForeignKey(x => x.NotificationID);
What fixed it (the correct way) was specifying the WithMany property:
builder.HasOne(x => x.Notification).WithMany(x => x.Recipients)
.HasForeignKey(x => x.NotificationID);
Hi After spending some time I could fix this problem by using ForeignKey attribute on public virtual Department Department { get; set; } property of Employee class.
Please see below code.
[Table("Employee")]
public class Employee
{
[DatabaseGenerated(System.ComponentModel.DataAnnotations.Schema.DatabaseGeneratedOption.Identity)]
public int Id { get; set; }
[Column("Name")]
public string Name { get; set; }
[Column("Department_ID")]
public int Department_ID { get; set; }
[ForeignKey("Department_ID")]
public virtual Department Department { get; set; }
}
This fixed my problem. Are there any other solution to fix this? Using fluent API?
For me, the issue was resolved by removing a (duplicate?) virtual property.
Using the OP's example:
public class Employee
{
public int Id { get; set; }
public string Name { get; set; }
public int Department_ID { get; set; }
public virtual Department Department { get; set; }
}
public class Department
{
public int ID { get; set; }
public string Name { get; set; }
public virtual ICollection<Employee> Employees { get; set; }
}
Turns into:
public class Employee
{
public int Id { get; set; }
public string Name { get; set; }
public int Department_ID { get; set; }
}
public class Department
{
public int ID { get; set; }
public string Name { get; set; }
public virtual ICollection<Employee> Employees { get; set; }
}
In my case I added a virtual property on top of the auto generated property
I fixed it by adding the NotMapped attribute to my property, or you could configure with fluent api
public partial class Control
{
[NotMapped]
public virtual ICollection<Control> Children { get => this.InverseParent; set => this.InverseParent = value; }
}
I had the same error, my issue was the FK was a long but I had it as an int in the model. EF generated a new column because it didn't match types on the FK so it assumed they weren't the same and went ahead with making another one but putting 1 at the end because there was already one with the proper name. Making sure the types matched resolved the issue for me.
This can be fixed simply by putting [NotMapped] annotation on your virtual properties.
public class Employee
{
[ForeignKey("Department")]
public int Department_ID
[NotMapped]
public virtual Department Department { get; set; }
}
And in you modelBuilder:
modelBuilder.Entity<Employee>(entity =>
{
entity.HasOne(e => e.Department);
});
Just flip this around if you want to call by Department.
We use the [NotMapped] annotation so that EF Core will disregard it when looking at your database.
I am new to MVC and i think someone answered this question before , so i apologize for re-posting it.
I've been a form based programmers for years , and now i am working on an MVC project for the first time, last 3 weeks i read a lot of books, articles, tutorials and watched a lot of videos about MVC.
Here is my question:
- I have 3 tables: Tasks, Customer and Employee
Each task has 1 customer and one employee assigned to it. I generated the Tasks table from an existing table i have on a SQL DB , but i followed "Code-First" to create the employee and Customer tables. I am not sure if i did the right relationships between those table. What i want to do is to display all tasks + the userNAME + CustomerName instead of UserID and CustomerID.
Here are my models:
Tasks:
public partial class Tasks
{
public string TaskID { get; set; }
public string Name { get; set; }
public System.DateTime StartDate { get; set; }
public Nullable<System.DateTime> DueDate { get; set; }
public Nullable<int> Complete { get; set; }
public string Description { get; set; }
public Nullable<int> Priority { get; set; }
public string Status { get; set; }
public Nullable<System.DateTime> AssignementDate { get; set; }
public Nullable<System.DateTime> CreationDate { get; set; }
[ForeignKey ("Employee")]
public string EmployeeID { get; set; }
public virtual ApplicationUser _User { get; set; }
[ForeignKey("Customer")]
public string CustomerID { get; set; }
public virtual CustomerModel _Customer { get; set; }
}
Customer:
public class CustomerModel
{
[Key]
public String ID { get; set; }
public String Number { get; set; }
}
Employee
public class EmployeeModel
{
[Key]
public string Id { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
}
Also How to access the employee first name from my Tasks controller.
Last question: is it ok to mix between models (Some code-first and some DB-first) Or should i follow one pattern.
Thanks a lot
You can use both pattern, but I recommend you my approach that you use CodeFirst, create entites to store data and viewmodels to display data:
public class Task
{
public int TaskID { get; set; }
//your other properties here...
public int EmployeeId { get; set; }
public int UserId { get; set; }
public int CustomerId { get; set; }
}
And in client lawyer, create ViewModel for Task model:
public class TaskViewModel
{
public Task Task { get; set; }
public EmployeeModel Employee { get; set; }
public ApplicationUser User { get; set; }
public CustomerModel Customer { get; set; }
}
In your GetTask() (Or LoadTasks()) method fill this view model:
public TaskViewModel GetTask(int id)
{
TaskViewModel model = new TaskViewModel();
model.Task = _db.GetTaskById(id);
model.Employee = _db.GetEmployeeById(model.Task.EmployeeId);
model.User = _db.GetUserById(model.Task.UserId);
model.Customer = _db.GetCustomerById(model.Task.CustomerId);
return model;
}
And now, you can get all data you want related to a task:
TaskId, TaskName, Created user's name + surname, Employee's name surname, Custemer's name + surname etc..
I am new to automapper. need some help to map from ViewModel to Entity.
Here's my user entity
public class User
{
public int Id { get; set; }
public string Firstname { get; set; }
public string Lastname { get; set; }
public DateTime CreatedDate { get; set; }
public string DisplayName { get; set; }
}
here's my ViewModel
public class UserViewModel
{
public string Email { get; set; }
public string Password { get; set; }
}
I create a map. its not working
CreateMap<UserLoginViewModel, User>()
.ForMember(dest=>dest.CreatedDate, DateTime.Now)
.ForMember(dest=>dest.DisplayName, "");
DisplayName and CreatedDate are required fields. since its not in the ViewModel, I will make DisplayName = "" and CreateDate = datetime.now.
I want to know if I can do it using the automapper, or I have to do it after the mapping.
please show me some sample code.
You mentioned that you have UserViewModel view model and User entity however your mapping configuration contains third type - UserLoginViewModel. Supposing that UserLoginViewModel is the same as UserViewModel, you should change you configuration as below.
Mapper.CreateMap<UserViewModel, User>()
.ForMember(dest=>dest.CreatedDate, t=> t.MapFrom(s=> DateTime.Now))
.ForMember(dest=>dest.DisplayName, t=> t.MapFrom(s=> ""));
AutoMapper wiki.
I'm trying out the ServiceStack MVC PowerPack, and am trying the included OrmLite ORM and am trying to get data from a table referenced by a foreign key without any idea how to do so.
In the OrmLite examples that use the Northwind database, for example, would it be possible to return a Shipper object that included the "ShipperTypeName" as a string looked up through the foreign key "ShipperTypeID"?
From http://www.servicestack.net/docs/ormlite/ormlite-overview, I'd like to add the ShipperName field to the Shipper class if possible:
[Alias("Shippers")]
public class Shipper : IHasId<int>
{
[AutoIncrement]
[Alias("ShipperID")]
public int Id { get; set; }
[Required]
[Index(Unique = true)]
[StringLength(40)]
public string CompanyName { get; set; }
[StringLength(24)]
public string Phone { get; set; }
[References(typeof(ShipperType))]
public int ShipperTypeId { get; set; }
}
[Alias("ShipperTypes")]
public class ShipperType : IHasId<int>
{
[AutoIncrement]
[Alias("ShipperTypeID")]
public int Id { get; set; }
[Required]
[Index(Unique = true)]
[StringLength(40)]
public string Name { get; set; }
}
To do this you would need to use Raw SQL containing all the fields you want and create a new Model that matches the SQL, so for this example you would do something like:
public class ShipperDetail
{
public int ShipperId { get; set; }
public string CompanyName { get; set; }
public string Phone { get; set; }
public string ShipperTypeName { get; set; }
}
var rows = dbCmd.Select<ShipperDetail>(
#"SELECT ShipperId, CompanyName, Phone, ST.Name as ShipperTypeName
FROM Shippers S INNER JOIN ShipperTypes ST
ON S.ShipperTypeId = ST.ShipperTypeId");
Console.WriteLine(rows.Dump());
Which would output the following:
[
{
ShipperId: 2,
CompanyName: Planes R Us,
Phone: 555-PLANES,
ShipperTypeName: Planes
},
{
ShipperId: 3,
CompanyName: We do everything!,
Phone: 555-UNICORNS,
ShipperTypeName: Planes
},
{
ShipperId: 4,
CompanyName: Trains R Us,
Phone: 666-TRAINS,
ShipperTypeName: Trains
}
]