Filter 过滤并更换清管器中的一个柱

假设我的数据看起来像

row1 cats val12 val13
row2 dogs val22 val23
row3 cats val32 val33
...

data = load 'file' AS (row:chararry, pets:charray, val2:charray, val3:charray);

筛选数据以仅保存“cats”行

felines = filter data by (pets matches 'cats');

现在将“猫”改为“狮子”

lions = foreach felines generate replace (pets, 'cats', 'lions');
dump lions;

(lions)
(lions)
...

我的目标是创建要添加到表中的新行

newFelines = foreach lions generate rows, lions, val1, val2;
                                    Error ^^^^^
"Error during parsing. Scalars can be only used with projections"

如何获得具有以下新行的集合

row1 lions val11 val12
row3 lions val31 val32

TIA，

逐行：

没有“chararry”或“charray”数据类型：

data = load 'file' USING  PigStorage(' ')  AS 
    (row:chararray, pets:chararray, val2:chararray, val3:chararray);

提取“猫”：

felines = filter data by (pets matches 'cats');

用“狮子”代替“猫”可以这样做：

lions = foreach felines generate row, REPLACE(pets, 'cats', 'lions'), val2, val3;

lions = foreach felines generate row, 'lions', val2, val3;

或者像这样：

lions = foreach felines generate row, REPLACE(pets, 'cats', 'lions'), val2, val3;

lions = foreach felines generate row, 'lions', val2, val3;

---

在这种情况下，您不需要提前过滤

狮子=foreach猫科动物生成行、替换（宠物、'cats'、'lions'）、val2、val3，它应该是
lions=FOREACH数据生成行，替换（pets，'cats，'lions'），val2，val3