按以下步骤进行：

allWines = LOAD 'winemag-data_first150k.csv' USING PigStorage(',') AS (id:chararray, country:chararray, description:chararray, designation:chararray, points:chararray, price:chararray, province:chararray, region_2:chararray, region_1:chararray, variety:chararray, winery:chararray);

--comments
--add below foreach to generate the values this will help you out to parse data correctly
--generate column in the same order as it is in the text file
allWines= FOREACH allWines GENERATE
id AS id,
country AS country,
description AS description,
designation AS designation,
points AS points,
price AS price, 
province AS provience,
region_2 AS region_2,
region_1 AS region_1,
variety AS variety,
winery AS winery;

allWinesNotNull = FILTER allWines BY price is not null;
allWinesNotNull2 = FILTER allWinesNotNull BY points is not null;
allWinesPriceSorted = ORDER allWinesNotNull2 BY price;
allWinesPriceTop5Sorted = LIMIT allWinesPriceSorted  5;
allWinesPricePoints = FOREACH allWinesPriceTop5Sorted GENERATE id, price;
DUMP allWinesPricePoints;
DESCRIBE allWinesPricePoints;

希望这能帮到你。如果有任何问题，请告诉我。