/**
   * Returns the name of column used for partitioning. If this is set to null, we use the table level replica groups.
   * Otherwise, we use the partition level replica groups.
   * TODO: use partition info from SegmentPartitionConfig
   *
   * @return Name of partitioning column.
   */
@Nullable
  public String getPartitionColumn() {
    return _partitionColumn;
  }
@Nullable
public String getPartitionColumn() {
return _partitionColumn;
}
@Nullable
public String getPartitionColumn() {
return _partitionColumn;
}
@Nullable
public String getPartitionColumn() {
return _partitionColumn;
}