constructor TTestSQLFunctions.Create( AEngine: TDBISAMEngine );
begin
 inherited Create;
 FEngine := AEngine;
 FServerVersion := '';
 with AEngine do begin
   with Functions.CreateFunction(ftString,'Test').Params do begin
     CreateFunctionParam(ftString);
   end;
   OnCustomFunction := DBISAMEngineCustomFunction;
 end;
end;