c# - Entity Framework 1:1 Relationship Identity Colums -

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i cannot life of me 2 separate tables save relationship , 2 identity columns. keep getting errors dependent property in referentialconstraint mapped store-generated column. column: 'olsterminalid'. can't imagine setup abnormal.

[datacontract]     public class olsdata {         private static readonly datetime theunixepoch = new datetime(1970, 1, 1, 0, 0, 0, 0, datetimekind.utc);      [databasegenerated(databasegeneratedoption.identity)]     public int olsdataid { get; set; }      [datamember(name = "id")]     public int id { get; set; }      public datetime timestamp { get; set; }      [datamember(name = "created")]     [notmapped]     public double created {         { return (timestamp - theunixepoch).totalmilliseconds; }         set { timestamp = theunixepoch.addmilliseconds(value); }     }      [inverseproperty("olsdata")]     [datamember(name = "terminal")]     public virtual olsterminal olsterminal { get; set; } }  [datacontract] public class olsterminal {     [databasegenerated(databasegeneratedoption.identity)]     public int olsterminalid { get; set; }      public int olsdataid { get; set; }      [datamember(name = "account")]     [notmapped]     public virtual olsaccount olsaccount { get; set; }      [datamember(name = "terminalid")]     public string terminalid { get; set; }      [datamember(name = "merchantid")]     public string merchantid { get; set; }      public virtual olsdata olsdata { get; set; } }   public class olsdatacontext : dbcontext {         protected override void onmodelcreating(dbmodelbuilder amodelbuilder) {             amodelbuilder.conventions.remove<pluralizingtablenameconvention>();         }          public olsdatacontext(string aconnectionstring) : base(aconnectionstring) {}         public dbset<olsdata> olsdata { get; set; }         public dbset<olsterminal> olsterminal { get; set; }         public dbset<olsaccount> olsaccount { get; set; }      }

it because 1:1 relationship in ef build on primary keys. fk in olsterminal table must olsterminalid , fk cannot autogenerated - must value of pk olsdata.

the reason why must done way requirement uniqueness of fk value in dependent entity build real 1:1 instead of 1:n. ef doesn't support unique constraints / candidate keys yet way how enforce uniqueness use place fk on pk of dependent entity.


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