Apache pig 在PIG中将数据从一个关系复制到另一个关系

我有两种关系：

关系A：

101,Ankit-Reddy,08022017
102,Siddarth-Battacharya,08022017
103,Rajesh-Khanna,08022017

关系B：

102,Ronit-Roy,09022017
103,Ranveer-Singh,09022017
107,sadiya-some,09022017
108,Raj-sharma,09022017

因此，在ID 102和103中，B中的日期不同，它是一个现有记录，但107108是新记录，所以它将保持不变。 如何在A中将其更新为最新版本

我的最终表格应该如下所示：

101,Ankit-Reddy,08022017
102,Ronit-Roy,08022017
103,Ranveer-Singh,08022017
107,sadiya-some,09022017
108,Raj-sharma,09022017

任何用于此的pig脚本。

• 只在一个会话中获取记录
• 只获取B中的记录，如B1
• 加入A和B，创建一个a1、b2、a3和C1的记录
• 合并A1、B1、C1

  A = LOAD 'test1.txt' USING PigStorage(',') AS (a1:int,a2:chararray,a3:chararray);
  B = LOAD 'test2.txt' USING PigStorage(',') AS (b1:int,b2:chararray,b3:chararray);
  
  A_JOIN = JOIN A BY a1 LEFT OUTER,B BY b1;
  A1 = FILTER A_JOIN BY b1 is null;
  
  B_JOIN  = JOIN A BY a1 RIGHT OUTER,B BY b1;
  B1 = FILTER B_JOIN BY a1 is null;
  
  C_JOIN = JOIN A BY a1,B by b1;
  C1 = FOREACH C_JOIN GENERATE a1,b2,a3;
  
  D = UNION A1,B1,C1;
  

A1

101,Ankit-Reddy,08022017

107,sadiya-some,09022017
108,Raj-sharma,09022017

102,Ronit-Roy,08022017
103,Ranveer-Singh,08022017

B1

101,Ankit-Reddy,08022017

107,sadiya-some,09022017
108,Raj-sharma,09022017

102,Ronit-Roy,08022017
103,Ranveer-Singh,08022017

C1

101,Ankit-Reddy,08022017

107,sadiya-some,09022017
108,Raj-sharma,09022017

102,Ronit-Roy,08022017
103,Ranveer-Singh,08022017