code: func (s *stmt) CheckNamedValue(nv *driver.NamedValue) error {
  	if nv.Name == bulk {
  		if ptr, ok := nv.Value.(**struct{}); ok {
  			switch ptr {
  			case &noFlushTok:
  				s.bulk, s.noFlush = true, true
  				return driver.ErrRemoveArgument
  			case &flushTok:
  				return driver.ErrRemoveArgument
  			}
  		}
  	}
  	return checkNamedValue(s.prmFieldSet, nv)
  }
docs: // Deprecated: see NamedValueChecker.
  //func (s *stmt) ColumnConverter(idx int) driver.ValueConverter {
  //}
  // CheckNamedValue implements NamedValueChecker interface.