public static String formatIntervalYearMonth(int v) {
    final StringBuilder buf = new StringBuilder();
    if (v >= 0) {
      buf.append('+');
    } else {
      buf.append('-');
      v = -v;
    }
    final int y = v / 12;
    final int m = v % 12;
    buf.append(y);
    buf.append('-');
    number(buf, m, 2);
    return buf.toString();
  }
Helper for CAST({date} AS VARCHAR(n)).
amoro-format-mixed/amoro-mixed-flink/amoro-mixed-flink-common/src/main/java/org/apache/amoro/flink/util/DateTimeUtils.java