I am building a platform using .NET CORE 2.1, and it is about questions and answers. Before I started I scaffolded my existing DB into the .net project so I got the model up and running.
Scaffold-DbContext "Server=(localdb)\mssqllocaldb;Database=MYDATABASE;Trusted_Connection=True;" Microsoft.EntityFrameworkCore.SqlServer -OutputDir Models
But it generated QUESTION and QUESTION_DETAIL with a many-to-one relation ship whereas QUESTION should only have 1 QUESTION DETAIl. But when I am trying to change it with the fluent API in my context it gives an error:
Cannot Convert lambda expression to type 'Type' because it is not a delegated type
Here are my 2 model classes
public partial class Question
{
public Question()
{
AnswerClientBot = new HashSet<AnswerClientBot>();
InverseOriginalQuestion = new HashSet<Question>();
QuestionFollowUpFollowUpQuestion = new HashSet<QuestionFollowUp>();
QuestionFollowUpOriginalQuestion = new HashSet<QuestionFollowUp>();
}
public int Id { get; set; }
public int BotInstanceId { get; set; }
public string LanguageCode { get; set; }
public string Question1 { get; set; }
public int? OriginalQuestionId { get; set; }
[ForeignKey("QuestionDetail")]
public int QuestionDetailId { get; set; }
public Instance BotInstance { get; set; }
public Question OriginalQuestion { get; set; }
public QuestionDetail QuestionDetail { get; set; }
public ICollection<AnswerClientBot> AnswerClientBot { get; set; }
public ICollection<Question> InverseOriginalQuestion { get; set; }
public ICollection<QuestionFollowUp> QuestionFollowUpFollowUpQuestion { get; set; }
public ICollection<QuestionFollowUp> QuestionFollowUpOriginalQuestion { get; set; }
}
public partial class QuestionDetail
{
public int Id { get; set; }
public int OriginalQuestionId { get; set; }
public string Topic { get; set; }
public string Intent { get; set; }
public string CustDetail01 { get; set; }
public string CustDetail02 { get; set; }
public string CustDetail03 { get; set; }
public string CustDetail04 { get; set; }
public string CustDetail05 { get; set; }
public string Keywords { get; set; }
public Question OriginalQuestion { get; set; }
}
And this is the context I am trying to change, the error occurs on
HasForeignKey(d => d.OriginalQuestionId)
modelBuilder.Entity<QuestionDetail>(entity =>
{
entity.ToTable("QuestionDetail", "Bot");
entity.Property(e => e.CustDetail01)
.HasColumnName("CUST_Detail01")
.HasMaxLength(250)
.IsUnicode(false);
entity.Property(e => e.CustDetail02)
.HasColumnName("CUST_Detail02")
.HasMaxLength(250)
.IsUnicode(false);
entity.Property(e => e.CustDetail03)
.HasColumnName("CUST_Detail03")
.HasMaxLength(250)
.IsUnicode(false);
entity.Property(e => e.CustDetail04)
.HasColumnName("CUST_Detail04")
.HasMaxLength(250)
.IsUnicode(false);
entity.Property(e => e.CustDetail05)
.HasColumnName("CUST_Detail05")
.HasMaxLength(250)
.IsUnicode(false);
entity.Property(e => e.Intent)
.HasMaxLength(250)
.IsUnicode(false);
entity.Property(e => e.Keywords)
.HasMaxLength(250)
.IsUnicode(false);
entity.Property(e => e.Topic)
.HasMaxLength(250)
.IsUnicode(false);
entity.HasOne(d => d.OriginalQuestion)
.WithOne(p => p.QuestionDetail)
.HasForeignKey(d => d.OriginalQuestionId)
.OnDelete(DeleteBehavior.ClientSetNull)
.HasConstraintName("FK_Bot_QuestionDetail_OriginalQuestionId");
});
Does anyone have any clue how I can fix this? Thank you!
Declare both classes with navigation properties to each other. Mark one of the tables (the dependent table) with the ForeignKey attribute on its Primary Key. EF infers 1-to-1 from this:
public class Question
{
...
// [ForeignKey("QuestionDetail")]
// public int QuestionDetailId { get; set; }
public QuestionDetail QuestionDetail { get; set; }
...
}
public partial class QuestionDetail
{
//public int Id { get; set; }
[ForeignKey("Question")]
public int QuestionId { get; set; }
...
public Question Question { get; set; }
}
So I found this Cannot convert lambda expression to type 'object' because it is not a delegate type stackoverflow post, and at the start I tried to strong type it but didn't know really how to but eventually I figured it out. So I changed it to HasForeignKey<Question>(d => d.OriginalQuestionId) which worked for me.
Related
I am quite new to EF Core 6.0. We currently have a projet to upgrade, we cannot change the actual tables (use by another program) so we use Database fisrt approch.
So I need to add some Permission on user (the database are in french) We curently have an UsagerEW table (user table) and we add an Permission Table and an joint table PermissionUsagerEW for the Many2Many. After doing Scaffold-dbContect here is the result:
UsagerEW (primary key is Code_Int)
public partial class UsagerEW
{
public UsagerEW()
{
PermissionUsagerEW = new HashSet<PermissionUsagerEW>();
RefreshToken = new HashSet<RefreshToken>();
}
public string Code { get; set; }
public string Nom { get; set; }
public string Email { get; set; }
public string ModeLogin { get; set; }
public string PasswordTemp { get; set; }
public DateTime? PasswordTempExp { get; set; }
public int code_int { get; set; }
public virtual ICollection<PermissionUsagerEW> PermissionUsagerEW { get; set; }
}
Pemrssion and PermissionUsagerEW
public partial class Permission
{
public Permission()
{
PermissionUsagerEW = new HashSet<PermissionUsagerEW>();
}
public int id { get; set; }
public string code { get; set; }
public string description { get; set; }
public int? moduleId { get; set; }
public virtual Module module { get; set; }
public virtual ICollection<PermissionUsagerEW> PermissionUsagerEW { get; set; }
}
public partial class PermissionUsagerEW
{
public int id { get; set; }
public int permissionId { get; set; }
public int usagerCodeInt { get; set; }
public virtual Permission permission { get; set; }
public virtual UsagerEW usagerCodeIntNavigation { get; set; }
}
That compile and I can "navigate with include" from UsagerEW and get an list of PermissionUsagerEW for a specific UsagerEW.
Now like I am in EF COre 6.0 that supposed to support Many2Many
I add this nav propertie in the Permnission class
public virtual ICollection<UsagerEW> UsagerEW { get; set; }
and this in the UsagerEW class:
public virtual ICollection<Permission> Permission { get; set; }
But I got execution error either I just try to load some user wintout any include:
UsagerEW user = _EWContext.UsagerEW.Where(u=>u.Code == usagerId).SingleOrDefault();
System.InvalidOperationException: 'Cannot use table
'PermissionUsagerEW' for entity type 'PermissionUsagerEW
(Dictionary<string, object>)' since it is being used for entity type
'PermissionUsagerEW' and potentially other entity types, but there is
no linking relationship. Add a foreign key to 'PermissionUsagerEW
(Dictionary<string, object>)' on the primary key properties and
pointing to the primary key on another entity type mapped to
'PermissionUsagerEW'.'
The FK are detect by the scaffold:
modelBuilder.Entity<PermissionUsagerEW>(entity =>
{
entity.HasOne(d => d.permission)
.WithMany(p => p.PermissionUsagerEW)
.HasForeignKey(d => d.permissionId)
.OnDelete(DeleteBehavior.ClientSetNull)
.HasConstraintName("FK_PermissionUsager_Permission");
entity.HasOne(d => d.usagerCodeIntNavigation)
.WithMany(p => p.PermissionUsagerEW)
.HasForeignKey(d => d.usagerCodeInt)
.OnDelete(DeleteBehavior.ClientSetNull)
.HasConstraintName("FK_PermissionUsager_Usager");
});
Any idea?
---EDIT 1
I change your code to reflect the scaffolded PermissionUsagerEW table:
//--UsagewrEW
modelBuilder.Entity<UsagerEW>()
.HasKey(u => u.code_int);
modelBuilder.Entity<UsagerEW>()
.HasMany(u => u.Permissions)
.WithMany(p => p.Users)
.UsingEntity<PermissionUsagerEW>(
p => p.HasOne(e => e.permission)
.WithMany()
.HasForeignKey(e => e.permissionId),
p => p.HasOne(p => p.usagerCodeIntNavigation)
.WithMany()
.HasForeignKey(e => e.usagerCodeInt)
);
modelBuilder.Entity<PermissionUsagerEW>()
.HasOne(p => p.usagerCodeIntNavigation)
.WithMany()
.HasForeignKey(p => p.usagerCodeInt);
When testing with
UsagerEW user = _EWContext.UsagerEW.Where(u=>u.Code == usagerId).Include(u => u.Permissions).SingleOrDefault();
Now I got this error:
Microsoft.Data.SqlClient.SqlException: 'Invalid column name
'UsagerEWcode_int'.'
I think EF tries to link something automatically. I do not have any UsagerEWcode_int in my solution.
EDIT2:
There is the SQL generated. Wierd column name and some repetition...
SELECT [u].[code_int], [u].[Administrateur], [u].[Code], [u].[Email], [u].[EmpContact], [u].[Inactif], [u].[KelvinConfig], [u].[LectureSeule], [u].[ModeLogin], [u].[Nom], [u].[ParamRole], [u].[Password], [u].[PasswordTemp], [u].[PasswordTempExp], [u].[RestreintCommContrat], [u].[RestreintProjet], [u].[Role], [u].[UsagerAD], [u].[doitChangerPW], [u].[estSuperviseur], [u].[idSuperviseur], [u].[infoSession], [u].[paramRole2], [u].[permsGrps], [t].[id], [t].[Permissionid], [t].[UsagerEWcode_int], [t].[permissionId0], [t].[usagerCodeInt], [t].[id0], [t].[code], [t].[description], [t].[moduleId]
FROM [UsagerEW] AS [u]
LEFT JOIN (
SELECT [p].[id], [p].[Permissionid], [p].[UsagerEWcode_int], [p].[permissionId] AS [permissionId0], [p].[usagerCodeInt], [p0].[id] AS [id0], [p0].[code], [p0].[description], [p0].[moduleId]
FROM [PermissionUsagerEW] AS [p]
INNER JOIN [Permission] AS [p0] ON [p].[permissionId] = [p0].[id]
) AS [t] ON [u].[code_int] = [t].[usagerCodeInt]
WHERE [u].[Code] = #__usagerId_0
ORDER BY [u].[code_int], [t].[id]
You can configure direct Many-to-Many relationships with an existing database, and you can have the linking entity in the model or exclude it. There are several examples in the docs. And you can leave the foreign key properties in the model, or you can replace them with shadow properties. But the Scaffolding code doesn't do any of this for you. It creates the simplest correct model for the database schema.
Also you usually should rename the entities and properties to align with .NET coding conventions.
Anyway something like this should work:
public partial class UsagerEW
{
public string Code { get; set; }
public string Nom { get; set; }
public string Email { get; set; }
public string ModeLogin { get; set; }
public string PasswordTemp { get; set; }
public DateTime? PasswordTempExp { get; set; }
public int code_int { get; set; }
public virtual ICollection<Permission> Permissions { get; } = new HashSet<Permission>();
}
public partial class Permission
{
public int Id { get; set; }
public string Code { get; set; }
public string Description { get; set; }
public int? ModuleId { get; set; }
//public virtual Module module { get; set; }
public virtual ICollection<UsagerEW> Users { get; } = new HashSet<UsagerEW>();
}
public partial class PermissionUsagerEW
{
public int Id { get; set; }
public int PermissionId { get; set; }
public int UsagerCodeInt { get; set; }
public virtual Permission Permission { get; set; }
public virtual UsagerEW User { get; set; }
}
public class Db : DbContext
{
protected override void OnModelCreating(ModelBuilder builder)
{
builder.Entity<UsagerEW>()
.HasKey(u => u.code_int);
builder.Entity<UsagerEW>()
.HasMany(u => u.Permissions)
.WithMany(p => p.Users)
.UsingEntity<PermissionUsagerEW>(
p => p.HasOne(e => e.Permission)
.WithMany()
.HasForeignKey(e => e.PermissionId),
p => p.HasOne(p => p.User)
.WithMany()
.HasForeignKey( e => e.UsagerCodeInt)
);
builder.Entity<PermissionUsagerEW>()
.HasOne(p => p.User)
.WithMany()
.HasForeignKey(p => p.UsagerCodeInt);
foreach (var prop in builder.Model.GetEntityTypes().SelectMany(e => e.GetProperties()))
{
prop.SetColumnName(char.ToLower(prop.Name[0]) + prop.Name.Substring(1));
}
base.OnModelCreating(builder);
}
But when you're working in a database-first workflow, there's a downside to deeply customizing the EF model: you loose the ability to regenerate the EF model from the database.
So you can use a "nice" customized EF model, or a "plain" scaffolded model. If you customize the model, you can no longer regenerate it, and need to alter it to match future database changes by hand.
You can apply some customizations, though, like the convention-based property-to-column and entity-to-table mappings in the example. But changing the generated "indirect many-to-many" to "direct many-to-many" will prevent you from regenerating the EF model through scaffolding.
I'm using Entity Framework Core with Code First approach but recieve following error when updating the database:
Introducing FOREIGN KEY constraint 'FK_AnEventUsers_Users_UserId' on table 'AnEventUsers' may cause cycles or multiple cascade paths. Specify ON DELETE NO ACTION or ON UPDATE NO ACTION, or modify other FOREIGN KEY constraints.
Could not create constraint or index. See previous errors.
My entities are these:
public class AnEvent
{
public int AnEventId { get; set; }
public DateTime Time { get; set; }
public Gender Gender { get; set; }
public int Duration { get; set; }
public Category Category { get; set; }
public int MinParticipants { get; set; }
public int MaxParticipants { get; set; }
public string Description { get; set; }
public Status EventStatus { get; set; }
public int MinAge { get; set; }
public int MaxAge { get; set; }
public double Longitude { get; set; }
public double Latitude { get; set; }
public ICollection<AnEventUser> AnEventUsers { get; set; }
public int UserId { get; set; }
public User User { get; set; }
}
public class User
{
public int UserId { get; set; }
public int Age { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public Gender Gender { get; set; }
public double Rating { get; set; }
public ICollection<AnEventUser> AnEventUsers { get; set; }
}
public class AnEventUser
{
public int AnEventId { get; set; }
public AnEvent AnEvent { get; set; }
public int UserId { get; set; }
public User User { get; set; }
}
public class ApplicationDbContext:DbContext
{
public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options):base(options)
{ }
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<AnEventUser>()
.HasOne(u => u.User).WithMany(u => u.AnEventUsers).IsRequired().OnDelete(DeleteBehavior.Restrict);
modelBuilder.Entity<AnEventUser>()
.HasKey(t => new { t.AnEventId, t.UserId });
modelBuilder.Entity<AnEventUser>()
.HasOne(pt => pt.AnEvent)
.WithMany(p => p.AnEventUsers)
.HasForeignKey(pt => pt.AnEventId);
modelBuilder.Entity<AnEventUser>()
.HasOne(eu => eu.User)
.WithMany(e => e.AnEventUsers)
.HasForeignKey(eu => eu.UserId);
}
public DbSet<AnEvent> Events { get; set; }
public DbSet<User> Users { get; set; }
public DbSet<AnEventUser> AnEventUsers { get; set; }
}
The issue I thought was that if we delete a User the reference to the AnEvent will be deleted and also the reference to AnEventUser will also be deleted, since there is a reference to AnEventUser from AnEvent as well we get cascading paths. But I remove the delete cascade from User to AnEventUser with:
modelBuilder.Entity<AnEventUser>()
.HasOne(u => u.User).WithMany(u => u.AnEventUsers).IsRequired().OnDelete(DeleteBehavior.Restrict);
But the error doesn't get resolved, does anyone see what is wrong? Thanks!
In your sample code in OnModelCreating you have declared modelBuilder.Entity<AnEventUser>().HasOne(e => e.User)... twice: at start of method and at end.
protected override void OnModelCreating(ModelBuilder modelBuilder)
{
modelBuilder.Entity<AnEventUser>() // THIS IS FIRST
.HasOne(u => u.User).WithMany(u => u.AnEventUsers).IsRequired().OnDelete(DeleteBehavior.Restrict);
modelBuilder.Entity<AnEventUser>()
.HasKey(t => new { t.AnEventId, t.UserId });
modelBuilder.Entity<AnEventUser>()
.HasOne(pt => pt.AnEvent)
.WithMany(p => p.AnEventUsers)
.HasForeignKey(pt => pt.AnEventId);
modelBuilder.Entity<AnEventUser>() // THIS IS SECOND.
.HasOne(eu => eu.User) // THIS LINES
.WithMany(e => e.AnEventUsers) // SHOULD BE
.HasForeignKey(eu => eu.UserId); // REMOVED
}
Second call overrides first. Remove it.
This is what I did from the answer of Dmitry,
and It worked for me.
Class:
public class EnviornmentControls
{
public int Id { get; set; }
...
public virtual Environment Environment { get; set; }
}
And it's Mapping
public EnviornmentControlsMap(EntityTypeBuilder<EnviornmentControls> entity)
{
entity.HasKey(m => m.Id);
entity.HasOne(m => m.Environment)
.WithMany(m => m.EnviornmentControls)
.HasForeignKey(m => m.EnvironmentID)
.OnDelete(DeleteBehavior.Restrict); // added OnDelete to avoid sercular reference
}
These solutions didn't work for my case, but I found a way. I am not quite sure yet if it is safe but there's just something that's happening with deleting. So I modified the generated Migration File instead of putting an override.
onDelete: ReferentialAction.Cascade
The reason I did this because all the overriding mentioned above is not working for me so I manually removed the code which relates to Cascading of Delete.
Just check which specific relation being mentioned at the error so you can go straightly.
Hope this will be able to help for some people who's having the same issue as mine.
public Guid? UsuarioId { get; set; }
builder.Entity<Orcamentacao>()
.HasOne(x => x.Usuario)
.WithMany(x => x.Orcamentacaos)
.OnDelete(DeleteBehavior.Restrict)
.IsRequired(false)
.HasForeignKey(x => x.UsuarioId);
I'm working with an existing database whose schema is fixed.
There are 3 many-to-many relations, Contact-Group, Contact-Department and Contact-Team.
There is a common table, ContactRelation that acts as the middle table for all 3 relations.
public class Contact
{
[Column("CtcID")]
public int Id { get; set; }
[Column("CtcFirstName")]
public string FirstName { get; set; }
[Column("CtcFamilyName")]
public string LastName { get; set; }
public virtual ICollection<ContactRelation> GroupRelations { get; set; }
public virtual ICollection<ContactRelation> DepartmentRelations { get; set; }
public virtual ICollection<ContactRelation> TeamRelations { get; set; }
}
public class Group
{
[Key, Column("GRID")]
public int Id { get; set; }
[Column("GRName")]
public string Name { get; set; }
public virtual ICollection<ContactRelation> ContactRelations { get; set; }
}
public class Department
{
[Key, Column("DEPID")]
public int Id { get; set; }
[Column("DEPName")]
public string Name { get; set; }
public virtual ICollection<ContactRelation> ContactRelations { get; set; }
}
public class Team
{
[Key, Column("TMID")]
public int Id { get; set; }
[Column("TransCode")]
public string TransCode { get; set; }
public virtual ICollection<ContactRelation> ContactRelations { get; set; }
}
public class ContactRelation
{
[Key]
[Column("CtcRelnID")]
public int Id { get; set; }
[Column("GRID")]
public int GroupId { get; set; }
[Column("DEPID")]
public int DepartmentId { get; set; }
[Column("TMID")]
public int TeamId { get; set; }
[Column("CUCtcID")]
public int ContactId { get; set; }
[Column("RCode")]
public string RoleCode { get; set; }
}
In my mapping, I have the following code:
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<Group>()
.HasMany(g => g.ContactRelations)
.WithRequired()
.HasForeignKey(r => r.GroupId);
modelBuilder.Entity<Department>()
.HasMany(c => c.ContactRelations)
.WithRequired()
.HasForeignKey(r => r.DepartmentId);
modelBuilder.Entity<Team>()
.HasMany(s => s.ContactRelations)
.WithRequired()
.HasForeignKey(r => r.TeamId);
modelBuilder.Entity<Contact>()
.HasMany(c => c.GroupRelations)
.WithRequired()
.HasForeignKey(r => r.ContactId);
modelBuilder.Entity<Contact>()
.HasMany(c => c.DepartmentRelations)
.WithRequired()
.HasForeignKey(r => r.ContactId);
modelBuilder.Entity<Contact>()
.HasMany(c => c.TeamRelations)
.WithRequired()
.HasForeignKey(r => r.ContactId);
}
I then try to execute the following query:
var ctc = repo.Contacts
.Include("GroupRelations")
.Include("DepartmentRelations")
.FirstOrDefault(c => c.FirstName.ToLower() == "jason");
and I keep getting error:
System.Data.SqlClient.SqlException:
Invalid column name 'Contact_Id1'.
Invalid column name 'Contact_Id'.
Invalid column name 'Contact_Id1'.
Invalid column name 'Contact_Id2'.
I read somewhere that a table cannot participate in more than one many-to-many relations. Is that true? Is it because the ContactRelation table is used more than once that I'm getting this error?
If so, what's the correct way to map these relations, without modifying the database schema.?
PS: I'm working with EF6.1
Thanks for your help.
Remove this mapping
modelBuilder.Entity<Contact>()
.HasMany(c => c.TeamRelations)
.WithRequired()
.HasForeignKey(r => r.ContactId);
and then try executing your query.
I am trying to create a foreign key relation ship with fluent syntax using EF code first approach.
My entities are as follows,
public partial class Defect
{
public int DefectID { get; set; }
public decimal ReleaseNo { get; set; }
public int BuildNo { get; set; }
public string Title { get; set; }
public string Description { get; set; }
public string StepsToReproduce { get; set; }
public int ApplicationModuleID { get; set; }
public int SeverityLevel { get; set; }
public string LoggedBy { get; set; }
public Nullable<System.DateTime> LoggedOn { get; set; }
public string LastModifiedBy { get; set; }
public Nullable<System.DateTime> LastModifiedOn { get; set; }
public string AssignedTo { get; set; }
public string Status { get; set; }
public string ResolutionNote { get; set; }
public Nullable<System.DateTime> ResolvedOn { get; set; }
public int ProjectID { get; set; }
public virtual SeverityIndex SeverityIndex { get; set; }
public virtual User LoggedByUser { get; set; }
public virtual User LastModifiedUser { get; set; }
public virtual User AssignedToUser { get; set; }
public virtual Project Project { get; set; }
}
public class DefectMap:EntityTypeConfiguration<Defect>
{
public DefectMap()
{
this.HasKey(d => d.DefectID);
this.ToTable("Defect");
this.Property(d => d.DefectID)
.IsRequired()
.HasColumnName("DefectID")
.HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity);
this.Property(d => d.Description)
.IsRequired()
.IsUnicode()
.IsVariableLength()
.HasMaxLength(2000)
.HasColumnName("Description")
.HasDatabaseGeneratedOption(DatabaseGeneratedOption.None);
this.Property(d => d.StepsToReproduce)
.IsOptional()
.IsUnicode()
.IsVariableLength()
.HasMaxLength(4000)
.HasColumnName("StepsToReproduce")
.HasDatabaseGeneratedOption(DatabaseGeneratedOption.None);
this.Property(d => d.LastModifiedBy)
.IsOptional()
.IsUnicode()
.IsVariableLength()
.HasMaxLength(10)
.HasColumnName("LastModifiedBy")
.HasDatabaseGeneratedOption(DatabaseGeneratedOption.None);
this.Property(d => d.AssignedTo)
.IsOptional()
.IsUnicode()
.IsVariableLength()
.HasMaxLength(10)
.HasColumnName("AssignedTo")
.HasDatabaseGeneratedOption(DatabaseGeneratedOption.None);
this.Property(d => d.Status)
.IsOptional()
.IsUnicode()
.IsVariableLength()
.HasMaxLength(50)
.HasColumnName("Status")
.HasDatabaseGeneratedOption(DatabaseGeneratedOption.None);
this.Property(d => d.ResolutionNote)
.IsOptional()
.IsUnicode()
.IsVariableLength()
.HasMaxLength(4000)
.HasColumnName("ResolutionNote")
.HasDatabaseGeneratedOption(DatabaseGeneratedOption.None);
this.HasRequired(p => p.Project).WithMany(p => p.DefectList).HasForeignKey(p => p.ProjectID);
this.HasRequired(s => s.SeverityIndex).WithMany(s => s.DefectList).HasForeignKey(s => s.SeverityLevel).WillCascadeOnDelete();
this.HasOptional(u => u.AssignedToUser).WithMany(u => u.AssignedToUserList).HasForeignKey(u => u.AssignedTo).WillCascadeOnDelete();
this.HasOptional(u => u.LastModifiedUser).WithMany(u => u.ModifiedByUserList).HasForeignKey(u => u.LastModifiedBy);
this.HasRequired(u => u.LoggedByUser).WithMany(u => u.LoggedByUserList).HasForeignKey(u => u.LoggedBy);
}
public partial class Project
{
public Project()
{
ApplicationModuleList = new List<ApplicationModule>();
DefectList = new List<Defect>();
UserList = new List<User>();
}
public int ID { get; set; }
public string ProjectName { get; set; }
public string ProjectManager { get; set; }
public Nullable<System.DateTime> ProjectStartDate { get; set; }
public Nullable<System.DateTime> ProjectEstimatedEndDate { get; set; }
public Nullable<System.DateTime> ProjectActualEndDate { get; set; }
public Nullable<int> ProjectBillingModel { get; set; }
public Nullable<decimal> ProjectEstimatedBudget { get; set; }
public Nullable<decimal> ProjectActualBudget { get; set; }
public Nullable<int> ProjectPortfolio { get; set; }
public Nullable<decimal> ProjectBillingRate { get; set; }
public Nullable<int> ProjectEstimatedManHours { get; set; }
public Nullable<int> ProjectActualManHours { get; set; }
public Nullable<int> ProjectIsApproved { get; set; }
public virtual ICollection<ApplicationModule> ApplicationModuleList { get; set; }
public virtual ICollection<Defect> DefectList { get; set; }
public virtual ICollection<User> UserList { get; set; }
public virtual BillingModel BillingModel { get; set; }
public virtual Portfolio Portfolio { get; set; }
public virtual ApprovalStatus ApprovalStatus { get; set; }
}
public class ProjectMap:EntityTypeConfiguration<Project>
{
public ProjectMap()
{
this.HasKey(p => p.ID);
this.ToTable("Projects");
this.Property(p => p.ID)
.HasColumnName("ID")
.HasDatabaseGeneratedOption(DatabaseGeneratedOption.Identity)
.IsRequired();
this.Property(p => p.ProjectName)
.HasColumnName("ProjectName")
.HasMaxLength(200)
.IsRequired()
.IsVariableLength()
.IsUnicode()
.HasDatabaseGeneratedOption(DatabaseGeneratedOption.None);
this.HasOptional(p => p.BillingModel).WithMany(p=>p.Projects).HasForeignKey(p => p.ProjectBillingModel).WillCascadeOnDelete();
this.HasOptional(p => p.Portfolio).WithMany(p=>p.Projects).HasForeignKey(p => p.ProjectPortfolio).WillCascadeOnDelete();
this.HasOptional(p => p.ApprovalStatus).WithMany(p=>p.Projects).HasForeignKey(p => p.ProjectIsApproved).WillCascadeOnDelete();
}
}
I am trying code first approach for database creation using fluent API.
However when I run the code I get error saying
*Introducing FOREIGN KEY constraint 'FK_dbo.User_dbo.Projects_ProjectID' on table 'User' may cause cycles or multiple cascade paths. Specify ON DELETE NO ACTION or ON UPDATE NO ACTION, or modify other FOREIGN KEY constraints. Could not create constraint. See previous errors*
The same error appears for AssignedTo column.
Here I am trying to implement logic where, A project can have many defects and a defect should have an associated Project ID (i.e one to many relationship between project and defect).
Can anyone suggest what is wrong with the code and where should I rectify the code to get things working?
Thanks in advance!!!
EF has Cascade delete on by default, and this will cause problems with your design - as per the error message.
Either add the following
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Conventions.Remove<OneToManyCascadeDeleteConvention>();
}
or include
WillCascadeOnDelete(false)
in your fluent API
I'm trying to define a many-to-many relationship explicitly. By explicitly, I mean that I'm defining the middle entity and configuring it using the Fluent API. Below is my code:
public class ContentType
{
public Int64 Id { get; set; }
public Guid SID { get; set; }
public String Name { get; set; }
public ContentType Parent { get; set; }
public Nullable<Int64> ParentId { get; set; }
public Category Category { get; set; }
public Nullable<Int64> CategoryId { get; set; }
public Boolean IsLocked { get; set; }
public virtual ICollection<ContentTypeColumn> ContentTypeColumns { get; set; }
}
public class Column
{
public Int64 Id { get; set; }
public Guid SID { get; set; }
public String SchemaName { get; set; }
public DataType DataType { get; set; }
public Int32 DataTypeId { get; set; }
public virtual ICollection<ContentTypeColumn> ContentTypeColumns { get; set; }
}
public class ContentTypeColumn
{
public Int64 Id { get; set; }
public Int64 ColumnId { get; set; }
public Column Column { get; set; }
public ContentType ContentType { get; set; }
public Int64 ContentTypeId { get; set; }
public Boolean IsRequired { get; set; }
public Boolean IsCalculated { get; set; }
public String Title { get; set; }
public Boolean IsSystem { get; set; }
public Expression Expression { get; set; }
public Int32 ExpressionId { get; set; }
public virtual ICollection<ColumnRule> Rules { get; set; }
}
public class ContentTypeConfiguration : EntityTypeConfiguration<ContentType>
{
public ContentTypeConfiguration()
{
this.ToTable("ContentType");
this.Property(x => x.Id).HasColumnName("ContentTypeId").IsRequired();
this.Property(x => x.Name).HasMaxLength(30);
this.HasOptional(x => x.Parent)
.WithMany()
.HasForeignKey(x => x.ParentId);
this.Property(x => x.SID).IsRequired();
}
}
public class ContentTypeColumnConfiguration : EntityTypeConfiguration<ContentTypeColumn>
{
public ContentTypeColumnConfiguration()
{
this.ToTable("ContentTypeColumn");
this.HasRequired(x => x.ContentType)
.WithMany()
.HasForeignKey(x => x.ContentTypeId);
this.Property(x => x.Title).HasMaxLength(50).IsRequired();
this.Property(x => x.Id).HasColumnName("ContentTypeColumnId");
}
}
For some reason, two foreign keys are being created on the resultant ContentTypeColumn table. One is a nullable foreign key, the other is non-nullable. I want only the latter to be generated, and I have no idea where the nullable key is coming from.
Any thoughts?
This is wrong:
this.HasRequired(x => x.ContentType)
.WithMany()
.HasForeignKey(x => x.ContentTypeId);
You have reverse navigation property so you must use int in WithMany or EF will probably create two relations:
this.HasRequired(x => x.ContentType)
.WithMany(y => y.ContentTypeColumns)
.HasForeignKey(x => x.ContentTypeId);
Btw. this mapping should not be needed at all because it is discovered automatically through default conventions.