Pig Latin 中 AVG() 函数的问题
Issue with AVG() function in Pig Latin
我正在尝试生成数据集中列出的性能 (double)
的 AVG()。我收到 ERROR 1066: Unable to open iterator for alias TEST
异常,我认为这是因为 TEST 为空且无法迭代。
代码:
flat_bus = FOREACH buss GENERATE near, name, FLATTEN(categories) AS category, stars;
bus_grouped = GROUP flat_bus BY category;
category_avg = FOREACH bus_grouped GENERATE group as grp, AVG(bus_grouped.stars);
TEST = LIMIT category_avg 10;
DUMP TEST;
我测试了群组功能,它成功转储如下所示:
应该从 flat_bus
获得星星
category_avg = FOREACH bus_grouped GENERATE group as grp, AVG(flat_bus.stars);
我正在尝试生成数据集中列出的性能 (double)
的 AVG()。我收到 ERROR 1066: Unable to open iterator for alias TEST
异常,我认为这是因为 TEST 为空且无法迭代。
代码:
flat_bus = FOREACH buss GENERATE near, name, FLATTEN(categories) AS category, stars;
bus_grouped = GROUP flat_bus BY category;
category_avg = FOREACH bus_grouped GENERATE group as grp, AVG(bus_grouped.stars);
TEST = LIMIT category_avg 10;
DUMP TEST;
我测试了群组功能,它成功转储如下所示:
应该从 flat_bus
获得星星category_avg = FOREACH bus_grouped GENERATE group as grp, AVG(flat_bus.stars);