private boolean mergeCardinalityViolationBranch(final Operator input) {
    if(input instanceof SelectOperator) {
      SelectOperator selectOp = (SelectOperator)input;
      if(selectOp.getConf().getColList().size() == 1) {
        ExprNodeDesc colExpr = selectOp.getConf().getColList().get(0);
        if(colExpr instanceof ExprNodeGenericFuncDesc) {
          ExprNodeGenericFuncDesc func = (ExprNodeGenericFuncDesc)colExpr ;
          return func.getGenericUDF() instanceof GenericUDFCardinalityViolation;
        }
      }
    }
    return false;
  }
@param totalFiles
         the totalFiles to set
ql/src/java/org/apache/hadoop/hive/ql/parse/SemanticAnalyzer.java