数据有15列，我选择了5列，这5列在问题“选择指定列”中提到，定义了上述问题的表
仅\u likes=foreach select指定的\u列生成$0，$1；
将only_likes存储到“test/only_likes”中；
group\u likes=组只喜欢0美元；
将组喜欢的内容存储到“测试/组喜欢”中；
max\u likes=foreach group\u likes generate group，max（仅\u likes.views）；
将maxïlikes存储到“test/maxïlikes”中；
result\ u likes=订购最多\ u likes$1 desc；
将结果存储到“test/result-likes”中；
我是用下面的命令做的

如果要保留与max likes对应的记录的所有字段，则必须执行以下操作：

dataAll = LOAD 'path' USING PigStorage('\t') AS (title:chararray, views:long, likes:long, dislikes:long, comment_count:long);

--group the data by title so that all records belonging to a title fall into a bag in the same record
dataGrouped = GROUP dataAll BY title;

--Using a nested foreach, order the contents of the bag by likes and pick the top record
dataDeduped = FOREACH dataGrouped {
                 soredtedByLikes = ORDER dataAll BY likes DESC;
                 maxLikesRecord = LIMIT soredtedByLikes 1;
                 GENERATE FLATTEN(maxLikesRecord);
              }

STORE dataDeduped INTO 'outputPath' USING PigStorage('\t');

嵌套foreach在这种情况下非常有用。点击此处查看更多信息：https://www.safaribooksonline.com/library/view/programming-pig/9781449317881/ch06.html （在该链接中搜索嵌套的foreach）。