Question

Flaglist = load '/flag.txt' using PigStorage (',') as (countryname:chararray, landmass:int, Zone:int, Area:int, Population:int, Language:int, Religion:int, Bars:int, stripes:int, Colours:int,red:int, green:int, blue:int,  gold:int, white:int, black:int, orange:int, mainhue:chararray, noofcircles:int, noofuprightcrosses:int, noofdiagonalcrosses:int, noofquarters:int, noofsunstarts:int, crescent:int, triangle:int, icon:int ,animate:int, text:int, topleft:chararray, bottomright:chararray );

Sumofbs = FOREACH Flaglist GENERATE Bars+stripes  ;
OrderBS = FOREACH Sumofbs GENERATE  Flaglist.countryname ;

ANS： -

2016-03-22 21：47：27,284 [主要] INFO org.apache.pig.backend.hadoop.executionengine.mapReduceLayer.MapReduceLauncher - 有些工作失败了！停止运行所有相关工作2016-03-22 21：47：27,358 [main] ERROR org.apache.pig.tools.grunt.Grunt - ERROR 1066：无法打开别名OrderBS的迭代器。后端错误： 标量在输出中有多行。第1名：（阿富汗，5,1,648,16,10,2,0,3,5,1,1,0,1,1,1,0，绿色，0,0,0,0,1 ，0,0,1,0,0，黑，绿）第2 （阿尔巴尼亚，3,1,29,3,6,6,0,0,3,1,0,0,1,0,1,0，红色，0,0,0,0,1,0， 0,0,1,0，红色，红色）

Answer 1

使用ORDER BY和LIMIT

Flaglist = load '/flag.txt' using PigStorage (',') as (countryname:chararray, landmass:int, Zone:int, Area:int, Population:int, Language:int, Religion:int, Bars:int, stripes:int, Colours:int,red:int, green:int, blue:int,  gold:int, white:int, black:int, orange:int, mainhue:chararray, noofcircles:int, noofuprightcrosses:int, noofdiagonalcrosses:int, noofquarters:int, noofsunstarts:int, crescent:int, triangle:int, icon:int ,animate:int, text:int, topleft:chararray, bottomright:chararray );

Sumofbs = FOREACH Flaglist GENERATE countryname,Bars+stripes as Total;
OrderBS = ORDER Sumofbs BY $1 DESC;
FinalOrderBS = LIMIT OrderBS 5;
DUMP FinalOrderBS;

使用PIG -how在desc中对两列的总和进行排序，并获得结果中的前5行

1 个答案: