@Override
  public int getMaxNumericScale() {
    // the max scale can't be greater than precision
    return DecimalType.MAX_PRECISION;
  }
Custom type system for Flink.

<p>Copied from flink-1.18.
amoro-format-mixed/amoro-mixed-flink/amoro-mixed-flink-common/src/main/java/org/apache/amoro/flink/planner/calcite/FlinkTypeSystem.java