c# - Difficulty only mapping base class in Entity Framework -

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i'm having difficulty figuring out how map base class in entity framework database, while preventing information classes inherit being mapped database.

i created simple example highlight difficulty there base worker class, , child class called engineer. reason, assume don't care store details of engineer... want database contain information in worker class.

so i've done following:

class program {     static void main(string[] args)     {         engineer e = new engineer();         e.name = "george";         e.focus = "software";          mydatabase db = new mydatabase();         e.save(db);     } }  public class mydatabase : dbcontext {     public dbset<worker> workers { get; set; }      public mydatabase() : base("mytempdb") { } }  [notmapped] public class engineer : worker {     public string focus { get; set; } }   public class worker {     [key]     [databasegeneratedattribute(databasegeneratedoption.identity)]     public int id { get; set; }     public string name { get; set; }      public bool save(mydatabase db)     {         try         {             if (db.workers.any(w => w.id == this.id))             {                 db.workers.attach(this);                 db.entry(this).state = system.data.entity.entitystate.modified;             }             else             {                 db.workers.add((worker)this);             }             db.savechanges();         }         catch (exception e)         {             console.writeline(e);             return false;         }          return true;     } }

i doing "database first" design, , database table looks like:

create table [dbo].workers (     [id] int not null primary key,      [name] nvarchar(200) null,      [discriminator] nvarchar(200) null )

however, when run program, still looking entity store engineer in. i've told not map it, hoping map base class database:

system.invalidoperationexception: mapping , metadata information not found entitytype 'consoleapplication10.engineer'.

i think might have map entity new worker entity before saving entity framework doesn't object's sub type—engineer.

for example:

public class worker {     [key]     [databasegeneratedattribute(databasegeneratedoption.identity)]     public int id { get; set; }     public string name { get; set; }      public static fromworker(worker worker)     {         // example of mapping entity         return new worker         {             id = worker.id,             name = worker.name,         };     }      public bool save(mydatabase db)     {         try         {             worker worker = worker.fromworker(this);              if (db.workers.any(w => w.id == worker.id))             {                 db.workers.attach(worker);                 db.entry(worker).state = system.data.entity.entitystate.modified;             }             else             {                 db.workers.add(worker);             }              db.savechanges();         }         catch (exception e)         {             console.writeline(e);             return false;         }          return true;     } }

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