private boolean deleting(String destination) {
    return destination.startsWith(Context.DestClausePrefix.DELETE.toString());
  }
Construct the data structures containing ExprNodeDesc for partition
columns and order columns. Use the input definition to construct the list
of output columns for the ReduceSinkOperator
ql/src/java/org/apache/hadoop/hive/ql/parse/SemanticAnalyzer.java