猪加入的独特性

Question

我有两张桌子：

Name_SSN和Phone_Address

Name_SSN包含Joe。

Phone_Address Joe999-999-9990日落佛罗里达乔999-9991日落佛罗里达吉姆999 999-9994 Sunny CA Jim 999 999 9994 Sunny CA Bob 999-9999-9999罗利VA

我想加入并得到: Joe

我对猪不熟悉，也不懂.

谢谢你的帮助，

克里斯

Answer 1

听起来你想在猪身上做一个内部连接。下面的代码应该对您有帮助：

NameSSNAddr.pig

--Load the two data files
namessn = LOAD 'Name_SSN.csv' USING PigStorage(',') AS (name:chararray, ssn:chararray);
phoneaddr = LOAD 'Phone_Address.csv' USING PigStorage(',') AS (name:chararray, phone:chararray, address:chararray);

--Perform the join of the two datasets on the "name" field
data_join = JOIN namessn BY name, phoneaddr BY name;

--The join combined all fields from both datasets.  
--We just want a few fields, so generate them specifically.
data = FOREACH data_join GENERATE namessn::name AS name, namessn::ssn AS ssn, phoneaddr::address AS address;

--You didn't say if you wanted the data distinct or not.
--If you want only one row per distinct user, use this alias.
data_distinct = DISTINCT data;

--Dump all of the aliases so you can see what's in them.
dump namessn;
dump phoneaddr;

dump data;
dump data_distinct;

来自dump namessn的输出

(Joe,xxx-xx-xxx1)
(Jim,xxx-xx-xxx2)
(Bob,xxx-xx-xxx3)

来自dump phoneaddr的输出

(Joe,999-999-9990,Sunset Florida)
(Joe,999-999-9991,Sunset Florida)
(Joe,999-999-9992,Sunset Florida)
(Jim,999-999-9994,Sunny CA)
(Jim,999-999-9994,Sunny CA)
(Bob,999-999-9999,Raleigh VA)

来自dump data的输出

(Bob,xxx-xx-xxx3,Raleigh VA)
(Jim,xxx-xx-xxx2,Sunny CA)
(Jim,xxx-xx-xxx2,Sunny CA)
(Joe,xxx-xx-xxx1,Sunset Florida)
(Joe,xxx-xx-xxx1,Sunset Florida)
(Joe,xxx-xx-xxx1,Sunset Florida)

来自dump data_distinct的输出

(Bob,xxx-xx-xxx3,Raleigh VA)
(Jim,xxx-xx-xxx2,Sunny CA)
(Joe,xxx-xx-xxx1,Sunset Florida)