@Explain(displayName = "filter expression", explainLevels = { Level.USER, Level.DEFAULT, Level.EXTENDED })
  public byte[] getFilterExp() {
    return filterExp;
  }
DDL task description for MSCK [REPAIR] TABLE ... [ADD|DROP|SYNC PARTITIONS] commands.
ql/src/java/org/apache/hadoop/hive/ql/ddl/misc/msck/MsckDesc.java