@Override
  public DecomposedPredicate decomposePredicate(JobConf jobConf, Deserializer deserializer,
                                                ExprNodeDesc predicate) {
    Preconditions.checkArgument(deserializer instanceof KuduSerDe);
    KuduSerDe serDe = (KuduSerDe) deserializer;
    Schema schema = serDe.getSchema();
    return KuduPredicateHandler.decompose(predicate, schema);
  }
Gives the storage handler a chance to decompose a predicate.
The storage handler should analyze the predicate and return the portion of it which
cannot be evaluated during table access.

@param jobConf contains a job configuration matching the one that will later be passed
              to getRecordReader and getSplits
@param deserializer deserializer which will be used when fetching rows
@param predicate predicate to be decomposed
@return decomposed form of predicate, or null if no pushdown is possible at all
kudu-handler/src/java/org/apache/hadoop/hive/kudu/KuduStorageHandler.java