PIG REGEX_EXTRACT_ALL 不工作

PIG REGEX_EXTRACT_ALL is not working

我有以下数据。

•   PRT_Edit & Set Shopping Cart in Retail

•   PRT_Confirm Shopping Cart for Goods

o   PRT-Ret_Process Supplier Invoice

o   PRT-Web_Overview of Orders

o   PRT_Update Outfirst Agreement

PRT_Axn_-Purchase and Requisition

数据有特殊符号,制表符space和spaces。我只想从此数据中提取文本部分:

PRT_Edit & Set Shopping Cart in Retail

PRT_Confirm Shopping Cart for Goods

PRT-Ret_Process Supplier Invoice

PRT-Web_Overview of Orders

PRT_Update Outfirst Agreement

我试过在 Pig 脚本中使用 REGEX_EXTRACT_ALL,如下所示,但它不起作用。

PRT = LOAD '/DATA' USING TEXTLOADER() AS (LINE:CHARARRAY);

Cleansed = FOREACH PRT GENERATE REGEX_EXTRACT_ALL(LINE,'[A-Z]*') AS DATA;

当我尝试转储 Cleansed 时,它没有显示任何数据。有谁能帮忙吗

您可以使用

Cleansed = FOREACH PRT GENERATE FLATTEN(
      REGEX_EXTRACT_ALL(LINE, '^[^a-zA-Z]*([a-zA-Z].*[a-zA-Z])[^a-zA-Z]*$'))
       AS (FIELD1:chararray), LINE;

正则表达式匹配以下内容:

  • ^ - 字符串开头
  • [^a-zA-Z]* - 字符 class
  • 中除拉丁字母外的 0 个或多个字符
  • ([a-zA-Z].*[a-zA-Z]) - 我们稍后将引用为 FIELD1 的捕获组,匹配:
    • [a-zA-Z].*[a-zA-Z] - 一个拉丁字母,然后是任何字符,尽可能多(使用贪婪的*,而不是*?懒惰的)
  • [^a-zA-Z]* - 0 个或多个非拉丁字母的字符
  • $ - 字符串结尾