I have a keyless data type I want to store in a table and manage using an API controller. However, an error is thrown in GetEdmModel:
[Keyless]
public class UserDocuments
{
[StringLength(30)]
public string UserID { get; set; } = string.Empty;
public Guid DocumentID { get; set; } = Guid.Empty;
public int Version { get; set; } = -1;
}
public static IEdmModel GetEdmModel()
{
ODataConventionModelBuilder builder = new ODataConventionModelBuilder();
builder.EntitySet<UserDocuments>("UserDocuments");
return builder.GetEdmModel();
}
I also tried this:
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<UserDocuments>()
.HasNoKey()
.ToTable("UserDocuments");
base.OnModelCreating(modelBuilder);
}
but it didn't work either; And as far as I have understood it this is equivalent to using the [Keyless] annotation for class UserDocuments.
So how do I need to implement this to get the functionality I want?
Related
public class UserDocuments
{
[Key]
[StringLength(30)]
public string UserID { get; set; } = string.Empty;
[Key]
public Guid DocumentID { get; set; } = Guid.Empty;
public UserType UserType { get; set; } = UserType.None;
public int Version { get; set; } = -1;
}
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<UserDocuments>()
.HasKey(x => new { x.UserID, x.DocumentID });
}
public static IEdmModel GetEdmModel()
{
ODataConventionModelBuilder builder = new ODataConventionModelBuilder();
builder.EntitySet<UserDocuments>("UserDocuments");
return builder.GetEdmModel();
}
The detail error message I get is
"The entity set 'UserDocuments' is based on type
'DocServer2.Shared.Models.UserDocuments' that has no keys defined."
I cannot figure what is wrong with my code; I checked related entries here on SO, but cannot see a difference. I don't think that should be the case, but is it a problem to mix string and Guid in a composite key?
Edit [08/07/22]
I need to add [key] annotations to the two properties of UserDocuments that make up the key.
Using EfCore 1.1, I am trying to have a autogenerated column using ValueGeneratedOnAdd. The problem is i am always getting value as "0". Do i have to manually do anything with the database table ?
Here is my model
public class Contact
{
public int Id { get; set; }
// This needs to be auto generated
public Int32 ContactIndex { get; set; }
public string FullName { get; set; }
public string Email { get; set; }
public DateTime LastAccessed { get; set; }
}
This is how my OnModelCreating looks like
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<Contact>()
.Property(c => c.ContactIndex)
.ValueGeneratedOnAdd();
// I tried following as well but it did't work
// .HasDefaultValueSql("IDENTITY(int, 1,1)");
;
}
ok I figured how to do it, but i really wanted to do that without using any annotations, and i still cannot figure out how to do it without annotations on model. So here is my solution.
You need to annotate your filed in the model like following
public class Contact
{
public int Id { get; set; }
[DatabaseGenerated(DatabaseGeneratedOption.Identity)]
public Int32 ContactIndex { get; set; }
public string FullName { get; set; }
public string Email { get; set; }
public DateTime LastAccessed { get; set; }
}
and add OnModelCreating in your context class. This will tell entity framework to ignore the column while adding or updating records. Make sure you calling method .ValueGeneratedAddOrUpdate( ). If you use only .ValueGeneratedAdd( ) you will get errors while making updates.
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<Contact>()
.Property(c => c.ContactIndex)
.ValueGeneratedOnAddOrUpdate();
;
}
Generate and run your migrations and your migrations should include "SqlServerValueGenerationStrategy.IdentityColumn"
protected override void Up(MigrationBuilder migrationBuilder)
{
migrationBuilder.AddColumn<int>(
name: "ContactIndex",
table: "Contact",
nullable: false,
defaultValue: 0)
.Annotation("SqlServer:ValueGenerationStrategy", SqlServerValueGenerationStrategy.IdentityColumn);
}
Using EntityFramework 4.3 w/POCOs.
how can I check if a property on a model is ignored or not.
In my DBContext Class Hierarchy I am ignoring a property by
modelBuilder.Entity<EClass>().Ignore (f => f.IgnoredProperty());
In my BaseContext class, I need to check if that property is ignored or not.
private void ProcessGlobalConvention(DbModelBuilder modelBuilder, IGlobalConvention convention)
{
modelBuilder.Entity<typeof(this.GetType())>("Ignored Property");
}
How can I do that?
Thanks
Use the EF power tools http://www.infoq.com/news/2013/10/ef-power-tools-beta4 to view your model. Is the property there?
Create a database. Is the column there?
Look at the Database.LogSqlEvents http://blog.oneunicorn.com/2013/05/08/ef6-sql-logging-part-1-simple-logging/ and parse the sql to see if the field name appears...
....unless you really want a code solution...?
IN WHICH CASE
New up your DbContext
Create one record and add it to the relevant DbSet
Get the DbEntityEntry
Look in CurrentValues.PropertyNames. Is your property there?
[TestMethod]
public void CreateDatabase()
{
Database.SetInitializer(new DropCreateDatabaseAlways<HomesContext>());
var db = new HomesContext();
Assert.IsFalse(db.Homes.Any());
var home = db.Homes.Create();
db.Homes.Add(home);
var entry = db.Entry(home);
Assert.IsTrue(entry.CurrentValues.PropertyNames.Contains("MaxResidents"));
Assert.IsTrue(entry.CurrentValues.PropertyNames.Contains("MaxStaff"));
Assert.IsFalse(entry.CurrentValues.PropertyNames.Contains("CurrentResidents"));
Assert.IsFalse(entry.CurrentValues.PropertyNames.Contains("CurrentStaff"));
}
public class HomesContext:DbContext
{
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<Home>().Ignore(x => x.CurrentResidents);
base.OnModelCreating(modelBuilder);
}
public DbSet<Home> Homes { get; set; }
}
public class Home
{
public int HomeId { get; set; }
public string HomeName { get; set; }
public int MaxResidents { get; set; }
public int MaxStaff { get; set; }
public int CurrentResidents { get; set; }
[NotMapped]
public int CurrentStaff { get; set; }
}
Heres the exception:
The model backing the 'ScannerContext' context has changed since the
database was created. Consider using Code First Migrations to update
the database (http://go.microsoft.com/fwlink/?LinkId=238269).
I get this everytime I run my application. I cant figure out what it means. I think it means something isn't mapped correctly, but I cant figure out what. I am using the code first model, and I have an existing database that I want totally custom mappings for. Right now, I have everything in my classes named the same as my database to eliminate possible cuases.
The Exception is thrown when I try to .Add() the entity to the context.
The Entity as it is in the Database
The Entity in my DataLayer
public class EAsset
{
public int i_GID { get; set; }
public EAssetType Type { get; set; }
public EOrgEnvironment Environment { get; set; }
public EUser Contact { get; set; }
public string s_Name { get; set; }
public string s_Role { get; set; }
public DateTime d_Added { get; set; }
public DateTime d_LastUpdated { get; set; }
public bool b_Retired { get; set; }
public EAsset()
{
Type = new EAssetType();
Environment = new EOrgEnvironment();
Contact = new EUser();
d_Added = DateTime.Now;
d_LastUpdated = DateTime.Now;
}
}
The Context Object (with attempted table mapping and key assignment)
public class ScannerContext : DbContext
{
public ScannerContext()
: base("LabDatabase") { }
public DbSet<EAsset> EAssets { get; set; }
public DbSet<EAssetType> EAssetTypes { get; set; }
public DbSet<EOrgEnvironment> EOrgEnvironments { get; set; }
public DbSet<EUser> EUsers { get; set; }
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<EAsset>().HasKey(k=>k.i_GID).ToTable("t_Assets");
modelBuilder.Entity<EAssetType>().HasKey(k => k.i_ID).ToTable("t_Asset_Types");
modelBuilder.Entity<EOrgEnvironment>().HasKey(k => k.i_ID).ToTable("t_Org_Environments");
modelBuilder.Entity<EUser>().HasKey(k => k.i_ID).ToTable("t_Users");
base.OnModelCreating(modelBuilder);
}
}
The Program
class Program
{
static void Main(string[] args)
{
EAsset Entity = new EAsset { s_Name = "jewri-pc" };
var sContext = new ScannerContext();
sContext.EAssets.Add(Entity);
sContext.SaveChanges();
}
}
For EF runtime version 4.0.3 / version 4.0
public class ScannerContext : DbContext
{
public ScannerContext()
: base("LabDatabase") { }
...
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
Database.SetInitializer<ScannerContext>(null); // <--- This is what i needed
...
base.OnModelCreating(modelBuilder);
}
}
With that code installed I am now chasing errors related to having all my relationships accounted for in the model. The FK Constraints are forcing me to add the missing relational items.
Found info here. They explain the importance a bit.
The model backing the <Database> context has changed since the database was created
Enable-Migrations -ContextTypeName EmployeeProject.Models.DepartmentContext
Means you have to write your project name.Models.Context name
It will work.
I'm creating a POCO model to use with entity framework code first CTP5. I'm using the decoration to make a property map to a PK column. But how can I define a PK on more then one column, and specifically, how can I control order of the columns in the index? Is it a result of the order of properties in the class?
Thanks!
NOTE:
As of 2019 this answer became non-valid for later EntityFramework versions.
You can specify the column order in the attributes, for instance:
public class MyEntity
{
[Key, Column(Order=0)]
public int MyFirstKeyProperty { get; set; }
[Key, Column(Order=1)]
public int MySecondKeyProperty { get; set; }
[Key, Column(Order=2)]
public string MyThirdKeyProperty { get; set; }
// other properties
}
If you are using the Find method of a DbSet you must take this order for the key parameters into account.
To complete the correct answer submitted by Slauma, you can use the HasKey method to specify an order for composite primary keys as well:
public class User
{
public int UserId { get; set; }
public string Username { get; set; }
}
public class Ctp5Context : DbContext
{
public DbSet<User> Users { get; set; }
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<User>().HasKey(u => new
{
u.UserId,
u.Username
});
}
}
If, like me, you prefer to use a configuration file you can do that in this way (based on Manavi's example):
public class User
{
public int UserId { get; set; }
public string Username { get; set; }
}
public class UserConfiguration : EntityTypeConfiguration<User>
{
public UserConfiguration()
{
ToTable("Users");
HasKey(x => new {x.UserId, x.Username});
}
}
Obviously you have to add the configuration file to your context:
public class Ctp5Context : DbContext
{
public DbSet<User> Users { get; set; }
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Configurations.Add(new UserConfiguration());
}
}
Use as a anonymous object:
modelBuilder.Entity<UserExamAttemptQuestion>().ToTable("Users").HasKey(o => new { o.UserId, o.Username });