Look the mapping below.
When I do :
session.Get<Customer>(theId); The result return is the right customer but the Address list is empty. In the database, I see the customer record and the address. The address record in the field Customer_id (generated by NHibernate) is not null and has the right value (id of the customer).
Class and Mapping
public class Customer
{
public virtual int Id { get; set; }
public virtual string LastName { get; set; }
public virtual Iesi.Collections.Generic.ISet<CustomerAddress> Address { get; set; }
public Customer()
{
Address = new Iesi.Collections.Generic.HashedSet<CustomerAddress>();
}
}
public class CustomerAddress
{
public virtual int Id { get; set; }
public virtual string Street { get; set; }
public virtual Customer Customer { get; set; }
}
public class CustomerMap : ClassMap<Customer>
{
public CustomerMap()
{
Id(x => x.Id).GeneratedBy.Native();
Map(x => x.LastName)
.Length(50)
.Not.Nullable();
HasMany(x => x.Address)
.AsSet()
.Inverse()
.Cascade.AllDeleteOrphan();
}
}
public class CustomerAddressMap : ClassMap<CustomerAddress>
{
public CustomerAddressMap()
{
Id(x => x.Id).GeneratedBy.Native();
Map(x => x.Street).Length(50);
References(x => x.Customer);
}
}
Lazy loading is enabled by default, which means you won't retrieve the addresses until you touch the Address property. You can disable lazy loading in your mapping with:
HasMany(x => x.Address)
.AsSet()
.Inverse()
.Cascade.AllDeleteOrphan()
.Not.LazyLoad();
Related
I have the following entities when I generate migration it creates two columns with name RestrictedCategoryId and RestrictedCategoryId1(FK). How to solve this issue to generate only one column with FK?
Note: I need OrderId in each entity.
`C#
public class Order
{
public Guid Id { get; set; }
public DateTime OrderDate { get; set; }
private List<Category> _categories;
public List<Category> Categories => _categories;
}
public class Category
{
public Guid Id { get; set; }
public string Code { get; set; }
public string Name { get; set; }
public Guid OrderId { get; set; }
public Order Order { get; set; }
private List<RestrictionCategory> _restrictedCategories;
public List<RestrictionCategory> RestrictedCategories => _restrictedCategories;
}
public class RestrictionCategory
{
public Guid Id { get; set; }
public string Name { get; set; }
public Guid OrderId { get; set; }
public Order Order { get; set; }
public Guid CategoryId { get; set; }
public Category Category { get; set; }
public Guid RestrictedCategoryId { get; set; }
public Category RestrictedCategory { get; set; }
}
public class OrderConfiguration : IEntityTypeConfiguration<Order>
{
public void Configure(EntityTypeBuilder<Order> builder)
{
builder.HasKey(o => o.Id);
builder.Property(o => o.Id).IsRequired();
}
}
public class CategoryConfiguration : IEntityTypeConfiguration<Category>
{
public void Configure(EntityTypeBuilder<Category> builder)
{
builder.HasKey(c => new { c.Id, c.OrderId });
builder.Property(o => o.Id).IsRequired();
builder.Property(o => o.OrderId).IsRequired();
builder.HasMany(c => c.RestrictedCategories).WithOne(cr => cr.Category)
.HasForeignKey(cr => new { cr.CategoryId, cr.OrderId
}).OnDelete(DeleteBehavior.NoAction);
}
}
public class RestrictionCategoryConfiguration : IEntityTypeConfiguration<RestrictionCategory>
{
public void Configure(EntityTypeBuilder<RestrictionCategory> builder)
{
builder.HasKey(c => new { c.Id, c.OrderId });
builder.Property(o => o.Id).IsRequired();
builder.Property(o => o.OrderId).IsRequired();
builder.HasIndex(cr => new { cr.RestrictedCategoryId, cr.OrderId });
}
}
`
The entities resembles to actual ones.
Actually you get two additional columns:
RestrictedCategoryId = table.Column<Guid>(nullable: false),
RestrictedCategoryId1 = table.Column<Guid>(nullable: true), // <--
RestrictedCategoryOrderId = table.Column<Guid>(nullable: true) // <--
Apparently EF Core Foreign Key Conventions doesn't play well with composite keys, so you have to explicitly configure the relationship - similar to what you did for the other relationship, just since your model has no corresponding collection navigation property you have to use HasMany with generic type argument and no parameters, e.g. inside CategoryConfiguration:
builder.HasMany<RestrictionCategory>()
.WithOne(cr => cr.RestrictedCategory)
.HasForeignKey(cr => new { cr.RestrictedCategoryId, cr.OrderId})
.OnDelete(DeleteBehavior.NoAction);
On EF core have Two tables(Page, Group) both have many to many relations with junction table GroupPage. Want to get all pages data with junction table related data based on groupId as like bellow.
If you construct your EF relation correctly you should not have a GroupPage entity.
See Entity Framework Database First many-to-many on how to construct your EF EDM correctly.
Once you have your EDM correctly mapped, you should have the classes
public class Page
{
public int Id { get; set; }
public ICollection<Group> Groups { get; set; }
...
}
public class Group
{
public int Id { get; set; }
public ICollection<Page> Pages { get; set; }
...
}
Then you just need to do the following
public IQueryable<Page> GetPages(int groupId)
{
return from group in _context.Groups
where group.Id == groupId
from page in group.Pages
select page;
}
The following syntax is self-descriptive. Here are the entities structure and Page Dto.
public class Page
{
public int Id { get; set; }
public ICollection<Group> Groups { get; set; }
...
}
public class Group
{
public int Id { get; set; }
public ICollection<Page> Pages { get; set; }
...
}
public class PageGroup
{
public int PageId { get; set; }
public Page Page { get; set; }
public int GroupId { get; set; }
public Group Group { get; set; }
}
public class PagesDto
{
public string Name { get; set; }
public int GroupId { get; set; }
public int PageId { get; set; }
public string Description { get; set; }
public string Tab { get; set; }
public string Module { get; set; }
public bool? IsActive { get; set; }
public bool? IsDefault { get; set; }
public PagesDto()
{
IsActive = false;
IsDefault = false;
}
}
Following function help us to get group related pages information.
public async Task<List<PagesDto>> GetAllPagesByGroupId(int selectedGroupId)
{
//get all pages
var pages = await _pagesRepository.GetAll().Select(p => new PagesDto {
PageId = p.Id,
Name = p.Name,
GroupId = 0
}).ToListAsync();
//get group ralated pages
var selectedGroupPageIds = _groupPagesRepository
.GetAll()
.Where(p => p.GroupId == selectedGroupId)
.Select(p => p.PageId);
//update page information base on group related pages info.
foreach (var item in pages.Where(p=>selectedGroupPageIds.Contains(p.PageId)))
{
item.GroupId = selectedGroupId;
}
return pages;
}
In code I have an object graph that looks like this:
public class Author
{
public int AuthorId { get; set; }
public string Name { get; set; }
public Address Address { get; set; }
}
public class Publisher
{
public int PublisherId { get; set; }
public string Name { get; set; }
public Address Address { get; set; }
}
public class Address
{
public int AddressId { get; set; }
public string Postcode { get; set; }
}
How do I model this in a relational database schema?
This needs to be a 0-1..1 relation, i.e. Authors and Publishers may either have or not have an Address.
Ideally Addresses would have to be referenced by either an Author or a Publisher but not both.
Massive bonus respect if you can model it in Entity Framework Core using navigation properties and have cascade delete remove the Address when an Author or Publisher is removed. (But I'm betting no one will be able to).
I'd list all the things I've tried, but the post would be so long no one would read it. It'll be quicker just to say I've tried everything I can think of.
There are many ways you can achieve the goal in EF Core. The key point is that Address will be the dependent end of the relationships and it will contain optional FKs to the principal entities Author and Publisher.
Here are the possible Address models and configurations:
(1) Address with explicit FK and navigation properties
Model:
public class Address
{
public int AddressId { get; set; }
public string Postcode { get; set; }
public int? AuthorId { get; set; }
public Author Author { get; set; }
public int? PublisherId { get; set; }
public Publisher Publisher { get; set; }
}
Configuration:
modelBuilder.Entity<Author>()
.HasOne(e => e.Address)
.WithOne(e => e.Author)
.HasForeignKey<Address>(e => e.AuthorId)
.OnDelete(DeleteBehavior.Cascade);
modelBuilder.Entity<Publisher>()
.HasOne(e => e.Address)
.WithOne(e => e.Publisher)
.HasForeignKey<Address>(e => e.PublisherId)
.OnDelete(DeleteBehavior.Cascade);
(2) Address with navigation properties only
Model:
public class Address
{
public int AddressId { get; set; }
public string Postcode { get; set; }
public Author Author { get; set; }
public Publisher Publisher { get; set; }
}
Configuration:
modelBuilder.Entity<Author>()
.HasOne(e => e.Address)
.WithOne(e => e.Author)
.HasForeignKey<Address>("AuthorId")
.OnDelete(DeleteBehavior.Cascade);
modelBuilder.Entity<Publisher>()
.HasOne(e => e.Address)
.WithOne(e => e.Publisher)
.HasForeignKey<Address>("PublisherId")
.OnDelete(DeleteBehavior.Cascade);
(3) Address with explicit FK properties only
Model:
public class Address
{
public int AddressId { get; set; }
public string Postcode { get; set; }
public int? AuthorId { get; set; }
public int? PublisherId { get; set; }
}
Configuration:
modelBuilder.Entity<Author>()
.HasOne(e => e.Address)
.WithOne()
.HasForeignKey<Address>(e => e.AuthorId)
.OnDelete(DeleteBehavior.Cascade);
modelBuilder.Entity<Publisher>()
.HasOne(e => e.Address)
.WithOne()
.HasForeignKey<Address>(e => e.PublisherId)
.OnDelete(DeleteBehavior.Cascade);
(4) Address without explicit FK and navigation properties
Model:
public class Address
{
public int AddressId { get; set; }
public string Postcode { get; set; }
}
Configuration:
modelBuilder.Entity<Author>()
.HasOne(e => e.Address)
.WithOne()
.HasForeignKey<Address>("AuthorId")
.OnDelete(DeleteBehavior.Cascade);
modelBuilder.Entity<Publisher>()
.HasOne(e => e.Address)
.WithOne()
.HasForeignKey<Address>("PublisherId")
.OnDelete(DeleteBehavior.Cascade);
Reference: Relationships
I'm having trouble accessing foreign key values in my view without using a partial.
I have tblProperty as Primary_Key and tblCustomer as foreign_key. I want to access the values of my foreign keys in my view but can't figure out why.
Model
public partial class tblProperty
{
public tblProperty()
{
this.Images = new HashSet<Image>();
this.tblCustomers = new HashSet<tblCustomer>();
}
public int propertyID { get; set; }
public string address { get; set; }
public string description { get; set; }
public virtual ICollection<Image> Images { get; set; }
public virtual ICollection<tblCustomer> tblCustomers { get; set; }
}
public partial class tblCustomer
{
public int customerID { get; set; }
public string name { get; set; }
public decimal contactNumber { get; set; }
public string notes { get; set; }
public Nullable<int> propertyID { get; set; }
public virtual tblProperty tblProperty { get; set; }
}
controller
public class propertyController : Controller
{
propertyDBEntities2 dc = new propertyDBEntities2();
public ActionResult List()
{
var properties = dc.tblProperties.Include(p => p.tblCustomers);
return View(properties.ToList());
}
public ActionResult Details(int id = 0)
{
var properties = dc.tblProperties.Include(p => p.tblCustomers);
tblProperty property = dc.tblProperties.Find(id);
tblCustomer customer = dc.tblCustomers.Find(id);
if (properties == null)
{
return HttpNotFound();
}
return View(dc.tblProperties.Find(id));
}
public ActionResult Create()
{
return View();
}
[HttpPost, ValidateAntiForgeryToken]
public ActionResult Create(tblProperty e)
{
if (ModelState.IsValid)
{
using (dc)
{
dc.tblProperties.Add(e);
dc.SaveChanges();
}
}
return RedirectToAction("List");
}
view
(like model.name is trying to access name from tblCustomer)
#model myProject.tblProperty
#Html.DisplayFor(model => model.name)
tblProperty doesnt have name.
I guess you need
#Html.DisplayFor(model => model.tblCustomer.name)
But just debug it or use intellisense
EDIT:
In my project I create a dtoClass Data Transfer Object
So for my avl class I have a dtoAvl
avl Class:
public partial class avl
{
public avl()
{
this.cars = new HashSet<cars>();
}
public long avl_id { get; set; }
public Nullable<long> car_id { get; set; }
public Nullable<decimal> speed { get; set; }
// this class contain info regarding the road
public virtual manila_rto manila_rto { get; set; }
public virtual ICollection<cars> cars { get; set; }
}
I create a dtoAvl
public class dtoAvl
{
public long Avl_ID { get; set; }
public long? Car_ID { get; set; }
public string RoadName { get; set; } // came from manila_rto
public int Speed { get; set; }
}
My controler
List<dtoAvl> result = db.avls.Select(
r => new dtoAvl
{
Avl_ID = r.Avl_ID,
Car_ID = r.Car_ID,
Speed = r.Speed,
// here is a propery but can be a list
RoadName = r.manila_rto.name
}).ToList();
return PartialView(result);
View:
#model IEnumerable<dtoAvl>
My database will run correctly, and I can input the data manually via SQL Server, however, when I try and pass the value in via my API (testing using Postman), the value won't pass into the database, it appears as "NULL".
I have a reports and a bookings tables.
This is the code for the reports:
public class Report
{
public Report()
{
Injuries = new List<Injury>();
this.Bookings = new HashSet<Booking>();
}
public int Id { get; set; }
public string Club1 { get; set; }
public string Club2 { get; set; }
public virtual ICollection<Injury> Injuries { get; set; }
public virtual ICollection<Booking> Bookings { get; set; }
}
Bookings:
public class Booking
{
//public Booking()
//{
// Reports = new List<Report>();
//}
public int Id { get; set; }
public string Club { get; set; }
public string PlayerName { get; set; }
public string PlayerNumber { get; set; }
public string Reason { get; set; }
public string Description { get; set; }
//public int? Report_Id { get; set; }
public Nullable<int> Report_Id { get; set; }
public virtual Report Report { get; set; }
//public virtual ICollection<Report> Reports { get; set; }
}
Controller:
//POST: api/Reports
[ResponseType(typeof(Report))]
public async Task<IHttpActionResult> PostReport(Report report)
{
if (!ModelState.IsValid)
{
return BadRequest(ModelState);
}
db.Reports.Add(report);
await db.SaveChangesAsync();
return CreatedAtRoute("DefaultApi", new { id = report.Id }, report);
}
I put the test information via Postman:
I'm not sure why Report_Id is showing as it's not required, however, Report_Id1 is the field that is connecting the Report and Booking together.
Since your foreign key doesn't follow convention (ReportId), you need to use the annotation [ForeignKey] or a fluent api configuration:
modelBuilder.Entity<Booking>()
.HasRequired(b => b.Report)
.WithMany(b => b.Bookings)
.HasForeignKey(p => p.Report_Id);
That is why EF is adding the second Report_ID1. https://msdn.microsoft.com/en-us/data/hh134698.aspx