I'm getting the error Wrong number of parameters specified for call to "myOnGetParamType" when trying to set a method to the OnGetParameterType event of TSQLDBWebDataProvider.

The event OnGetParameterType is of type TGetParamTypeEvent, defined in sqldbwebdata.pp:

TGetParamTypeEvent = Procedure (Sender : TObject;
  Const ParamName,AValue: String; Var AType : TFieldtype) of object;

My method is this:

procedure myOnGetParamType(Sender : TObject; Const ParamName, AValue : String;
   Var AType : TFieldtype);

As you can see, my method has the same structure of TGetParamTypeEvent.

Why I'm getting this error?

Sorry, forgor to add the @ in the assignemnt, it should be @myOnGetParamType. :)