c# - SQLite-Net Extensions how to correctly update object recursively -

i using sqlite-net pcl sqlite-net extensions development of application using xamarin.

i have 1 many relationship between 2 classes a , b defined follows:

   public class {      [primarykey, autoincrement]     public int id     {         get;         set;     }      public string name     {         get;         set;     }      [onetomany(cascadeoperations = cascadeoperation.all)]     public list<b> sons     {         get;         set;     }      public a()     {     }      public a(string name, list<b> sons)     {         name = name;         sons = sons;     }  }  public class b {      [primarykey, autoincrement]     public int id     {         get;         set;     }      public string name     {         get;         set;     }      [foreignkey(typeof(a))]     public int fatherid     {         get;         set;     }      [manytoone]     public father     {         get;         set;     }      public b()     {     }      public b(string name)     {         name = name;     }  } 

what do, retrieve object of type a database, remove 1 of sons objects of type b , update database accordingly. have tried:

        var sons = new list<b>         {             new b("uno"),             new b("due"),             new b("tre"),         };          1 = new a("padre", sons);          using (var conn = databasestore.getconnection())         {             conn.deleteall<a>();             conn.deleteall<b>();              conn.insertwithchildren(one, true);              retrieved = conn.getwithchildren<a>(one.id);             retrieved.sons.removeat(1);         }          using (var conn = databasestore.getconnection())         {             var retrieved = conn.getwithchildren<a>(one.id);             retrieved.sons.removeat(1); //"due"              //conn.updatewithchildren(retrieved);             conn.insertorreplacewithchildren(retrieved, true);         } 

the problem both updatewithchildren , insertorreplacewithchildren the object not removed database, it's foreign key nulled. possible make delete son object?

you're not trying delete object @ all. you're removing relationship between 2 objects, nothing stops having more objects related of them, deleting not correct may break other relationships.

it should more this:

using (var conn = databasestore.getconnection()) {     var retrieved = conn.getwithchildren<a>(one.id);     var due = retrieved.sons[1];      // not required if foreign key in other end,     // usual way other scenario     // retrieved.sons.remove(due);     // conn.updatewithchildren(retrieved);      // delete object if it's no longer required exist in database     conn.delete(due); }