I have a bit of an issue and I need to know what the best design is for EF.
I have a Attribute model:
public enum TargetType
{
Attributes,
Availability,
Master
}
public class Attribute
{
public int Id { get; set; }
public int CriteriaId { get; set; }
[Required, MaxLength(100)] public string Name { get; set; }
[MaxLength(100)] public string Description { get; set; }
public TargetType Target { get; set; }
public virtual IList<Formula> Formulas { get; set; }
}
It has a list of Formulas:
public class Formula
{
public int Id { get; set; }
public int AttributeId { get; set; }
[Required]
[MaxLength(5)]
public string Operator { get; set; }
[Required]
[MaxLength(255)]
public string Expression { get; set; }
[MaxLength(100)]
public string Field { get; set; }
}
Which I match up in my DbContext like this:
modelBuilder.Entity<Attribute>().HasMany(m => m.Formulas).WithOptional().HasForeignKey(m => m.AttributeId);
The problem is, I now need to have Formulas as a separate property to another class Answer like this:
public class Answer
{
public int Id { get; set; }
public int QuestionId { get; set; }
[Required]
[MaxLength(255)]
public string Text { get; set; }
public int Order { get; set; }
public virtual IList<Formula> Formulas { get; set; }
}
The problem with this is Formula has AttributeId as a foreign key, so I can't really use the Formula model. I would have to create a new one like:
public class AnswerFormula
{
public int Id { get; set; }
public int AnswerId { get; set; }
[Required]
[MaxLength(5)]
public string Operator { get; set; }
[Required]
[MaxLength(255)]
public string Expression { get; set; }
[MaxLength(100)]
public string Field { get; set; }
}
But this seems counter-intuitive. So my question is, has anyone come across this before? If so, how did you solve the issue? For me, the problem is further enhanced when I start to use view models and factories.
Related
I have the following class that I want to use as my data context in Entity Framework:
public class AggregateRecord : IAggregateRecord
{
[Key]
public int AggregateRecordID { get; set; }
public DateTime? InsertDate { get; set; } = DateTime.Now;
public DateTime BookingDate { get; set; }
public string AmountTypeName { get; set; }
public int? UnifiedInstrumentCode { get; set; }
public double? Amount { get; set; }
public string BookingAccountID { get; set; }
public string AccountCurrency { get; set; }
public string ClientCurrency { get; set; }
public string AffectsBalance { get; set; }
public string AssetType { get; set; }
public string UnderlyingInstrumentSubType { get; set; }
public string InstrumentSymbol { get; set; }
public string InstrumentSubType { get; set; }
public string UnderlyingInstrumentAssetType { get; set; }
public string UnderlyingInstrumentDescription { get; set; }
public string UnderlyingInstrumentSymbol { get; set; }
public string UnderlyingInstrumentUic { get; set; }
public double? AmountAccountCurrency { get; set; }
public string AmountClientCurrency { get; set; }
public string InstrumentDescription { get; set; }
public virtual ICollection<InstrumentInfo> InstrumentInfo { get; set; }
}
public class InstrumentInfo
{
[Key]
public int InstumentInfoID {get;set;}
public string SomeInformation { get; set; }
public int AggregateRecordID { get; set; }
public virtual AggregateRecord AggregateRecord { get; set; }
}
I have studies the examples provided for EF6 but I still have the problem that when I try to update my migration that I get the following error:
One or more validation errors were detected during model generation:
There are no primary or candidate keys in the referenced table 'dbo.AggregateRecords' that match the referencing column list in the foreign key 'FK_dbo.InstrumentInfoes_dbo.AggregateRecords_AggregateRecordID'.
Could not create constraint or index. See previous errors.
How do I have to define the classes so that InstrumentInfo can be accessed via a navigation property?
public class InstrumentInfo
{
[Key]
public int InstumentInfoID {get;set;}
public string SomeInformation { get; set; }
public int AggregateRecordId { get; set; }
public virtual AggregateRecord AggregateRecord { get; set; }
}
Seems you forgot "public"
I "solved" the problem. It's weird, but maybe it helps somebody in future that's why I answer my own question.
I renamed my class AggregateRecord to AggregateEntry. Performed the Add-Migration and Update-Database, with the new renamed class name. And it worked.
It looks like there was some problem with the migration definition or whatsoever, but it solved it.
In the end, I renamed it back to the original name, did the same procedure again and, voila, it works.
#Dennis Spade: Thanks for your effort, without your hint it would have taken me even more time to find the real "problem".
In simple relational terms, I want each entry of ContractDetails to be assigned to either a Site OR a Company, not both at the same time, and one of them must be selected or there is no link at all. I'm not quite sure how to represent this in entity framework. My Model at Present:
Company Model:
public class Company
{
public int ID { get; set; }
public string Company_Name { get; set; }
public string Company_Prefix { get; set; }
public virtual ICollection<Site> Sites { get; set; }
}
Contract Details Model:
public class ContractDetails
{
public int ContractDetailsID { get; set; }
public int ContractTypeID { get; set; }
public int ContractRenewalPeriodID { get; set; }
public int? CompanyID { get; set; }
public int? SiteID { get; set; }
[Required, StringLength(10)]
public string Reference { get; set; }
[Display(Name = "Contract Start Date"), DataType(DataType.Date)]
public DateTime? Contract_Start_Date { get; set; }
[Display(Name = "Contract End Date"), DataType(DataType.Date)]
public DateTime? Contract_End_Date { get; set; }
[Column(TypeName = "text")]
public string Notes { get; set; }
public string Direct_Debit_Reference { get; set; }
public virtual Company Company { get; set; }
public virtual Site Site { get; set; }
public virtual ContractType ContractType { get; set; }
public virtual ContractRenewalPeriod ContractRenewalPeriod { get; set; }
}
Site Model:
public class Site
{
public int ID { get; set; }
public string Site_Name { get; set; }
public string Site_TelephoneNumber { get; set; }
public string Site_City { get; set; }
public int CompanyID { get; set; }
public virtual Company Company { get; set; }
}
Just implement the IValidatableObject on ContractDetails class. On Validate method put the validation logic. If the object is not valid you must return a collection of ValidationResult. when saving the object, EF will execute the Validate method and verify that your ContractDetails object is coherent.
I've been working on this for a while now and i still haven't come up with a good idea.
I have the fallowing 3 types Project, User and Result. A user and a project can have multiple results. My problem now is that a result can be of multiple types (12 right now and that can change). I have no idea how i'm supposed to structure this the only things that this results have in common is a type and an Id and i want a table for each of the different 12 types.
So what i have until now is this.
Project
public class Project :ITypedEntity<ProjectType>
{
public int Id { get; set; }
public string Name { get; set; }
public string Nationality { get; set; }
public virtual ProjectType Type { get; set; }
public string TitleEn { get; set; }
public string TitleRo { get; set; }
public string Acronym { get; set; }
public string ContractNo { get; set; }
public virtual ActivityField ActivityField {get;set;}
public string SummaryEn { get; set; }
public string SumarryRo { get; set; }
public DateTime StartDate { get; set; }
public DateTime EndDate { get; set; }
public decimal Value { get; set; }
public bool IsPartner { get; set; }
public ICollection<User> Team{get;set;}
public string Website {get;set;}
public ICollection<INamedEntity> Results;
}
Result
public class Result:ITypedEntity<ResultType>
{
public int Id { get; set; }
public string Name{get;set;}
public ResultType Type { get; set; }
}
User
public class User:Person
{
public int CNP { get; set; }
public virtual Faculty Faculty { get; set; }
public bool IsUSAMV {get;set;}
public virtual ICollection<INamedEntity> Results {get;set;}
public virtual ICollection<Project> Projects {get;set;}
}
I don't think this helps but i'll paste them anyway
public interface INamedEntity:IEntity
{
string Name{get;set;}
}
public interface ITypedEntity<TType>:INamedEntity{
TType Type { get; set; }
}
public interface IEntity
{
int Id { get; set; }
}
Update 1
Some results types
public class BookChapter:INamedEntity
{
public int Id { get; set; }
public string Name { get; set; }
public virtual Book Book {get;set;}
public int PagesInChapter {get;set;}
public string Pagination {get;set;}
}
public class Book:INamedEntity
{
public int Id { get; set; }
public string Name { get; set; }
public ICollection<Person> Authors { get; set; }
public int Year { get; set; }
public Publisher Publisher {get;set;}
public int NumberOfPages { get; set; }
public string Pagination { get; set; }
public int ISBN { get; set; }
}
public class Patent:ITypedEntity<PatentType>
{
public int Id { get; set; }
public string Name { get; set; }
public virtual ICollection<Person> Authors { get; set; }
public virtual Person Holder{get;set;}
public string Number{get;set;}
public virtual PatentType Type { get; set; }
}
Sorry if the question is not clear, i'll update it with any other information you need.
Thanks.
Weird question here.
I have a bad situation with a database I can't change.
[Table("PROJTABLE")]
public class Certifikat {
[Key]
public long Recid { get; set; }
public String DATAAREAID { get; set; }
public String Projid { get; set; }
public virtual StandardAndScope StandardInfo { get; set; }
}
[Table("DS_CRT_PROJSTANDARDSCOPE")]
public class StandardAndScope {
[Key]
public long RECID { get; set; }
public String DATAAREAID { get; set; }
public String Standard { get; set; }
public String Scope { get; set; }
}
I have an optional one-to-many relationship from Certifikat to StandardAndScope. However! It's only one-to-many if the DATAAREAID column is a certain value ("crt").
Do I have any way of telling EntityFramework only to map rows where the value of that column is crt?
I want to create my first application using the EF 4.1 Code First Model. I want to model a magazine subscription but just want to check that my POCO classes are fit for purpose.
The following are my classes. Am I missing anything?
Should Customer be a member of Subscription or should it be just that List be a member of Customer?
Thanks.
public class Subscription
{
public int SubscriptionID { get; set; }
public string CardNumber { get; set; }
public DateTime StartDate { get; set; }
public DateTime EndDate { get; set; }
public decimal NetPrice { get; set; }
public decimal Tax { get; set; }
public decimal Discount { get; set; }
public string PromotionalCode { get; set; }
public Customer Customer{ get; set; }
}
public class Customer {
public int CustomerID { get; set; }
public string Title { get; set; }
public string FirstName { get; set; }
public string LastName { get; set; }
public PostalAddress PostalAddress { get; set; }
public string EmailAddress { get; set; }
public string Telephone { get; set; }
public string Mobile { get; set; }
public DateTime DateOfBirth { get; set; }
public string Username { get; set; }
public string Password { get; set; }
public string SecurityQuestion { get; set; }
public string SecurityAnswer { get; set; }
public bool Valid { get; set; }
public IList<Subscription> Subscriptions { get; set; }
public bool MailMarketing { get; set; }
public bool PartnerMailMarketing { get; set; }
}
public class PostalAddress
{
public int ID { get; set; }
public string Address1 { get; set; }
public string Address2 { get; set; }
public string Address3 { get; set; }
public string City { get; set; }
public string Postcode { get; set; }
public string Region { get; set; }
public string Country { get; set; }
}
If a Customer have X suscriptions, every suscription should have the customerID so you need that in your Suscription class (public int CustomerID {get; set;}).
OTOH, I think that you have to put that Customer reference as virtual and the suscription one (I don't know why).
Maybe Im wrong but that works for me.
Anyway, what's your problem?
Your models look correct. You don't necessarily need the Customer property in the Subscription class, but it does help if you want to retrieve a specific Subscription and then want to find the customer that is tied to that subscription. In that instance you can then do var customer = mySub.Customer instead of querying for a customer with the specific subscription id.