code: func splitDateTime(format string) (seps []string, fracStr string) {
  	index := GetFracIndex(format)
  	if index > 0 {
  		fracStr = format[index+1:]
  		format = format[:index]
  	}
  
  	seps = ParseDateFormat(format)
  	return
  }
docs: // See https://dev.mysql.com/doc/refman/5.7/en/date-and-time-literals.html.
  // The only delimiter recognized between a date and time part and a fractional seconds part is the decimal point.