code: func (statement *Statement) SQL(query interface{}, args ...interface{}) *Statement {
  	switch query.(type) {
  	case (*builder.Builder):
  		var err error
  		statement.RawSQL, statement.RawParams, err = query.(*builder.Builder).ToSQL()
  		if err != nil {
  			statement.lastError = err
  		}
  	case string:
  		statement.RawSQL = query.(string)
  		statement.RawParams = args
  	default:
  		statement.lastError = ErrUnSupportedSQLType
  	}
  
  	return statement
  }
docs: // SQL adds raw sql statement