docs: @Override
      public List<Statement> getStatements() {
          List<Statement> result = new LinkedList<>();
          for (ShardingExecuteGroup<StatementExecuteUnit> each : getExecuteGroups()) {
              result.addAll(Lists.transform(each.getInputs(), new Function<StatementExecuteUnit, Statement>() {
                  
                  @Override
                  public Statement apply(final StatementExecuteUnit input) {
                      return input.getStatement();
                  }
              }));
          }
          return result;
      }