Apache Pig - Operator Lintas
Itu CROSSoperator menghitung produk silang dari dua atau lebih relasi. Bab ini menjelaskan dengan contoh bagaimana menggunakan operator silang dalam Pig Latin.
Sintaksis
Diberikan di bawah ini adalah sintaks dari CROSS operator.
grunt> Relation3_name = CROSS Relation1_name, Relation2_name;
Contoh
Asumsikan kita memiliki dua file yaitu customers.txt dan orders.txt dalam /pig_data/ direktori HDFS seperti yang ditunjukkan di bawah ini.
customers.txt
1,Ramesh,32,Ahmedabad,2000.00
2,Khilan,25,Delhi,1500.00
3,kaushik,23,Kota,2000.00
4,Chaitali,25,Mumbai,6500.00
5,Hardik,27,Bhopal,8500.00
6,Komal,22,MP,4500.00
7,Muffy,24,Indore,10000.00
orders.txt
102,2009-10-08 00:00:00,3,3000
100,2009-10-08 00:00:00,3,1500
101,2009-11-20 00:00:00,2,1560
103,2008-05-20 00:00:00,4,2060
Dan kami telah memuat dua file ini ke Pig dengan relasi customers dan orders seperti gambar dibawah.
grunt> customers = LOAD 'hdfs://localhost:9000/pig_data/customers.txt' USING PigStorage(',')
as (id:int, name:chararray, age:int, address:chararray, salary:int);
grunt> orders = LOAD 'hdfs://localhost:9000/pig_data/orders.txt' USING PigStorage(',')
as (oid:int, date:chararray, customer_id:int, amount:int);
Sekarang, mari kita dapatkan hasil perkalian silang dari kedua relasi ini menggunakan cross operator pada dua relasi ini seperti yang ditunjukkan di bawah ini.
grunt> cross_data = CROSS customers, orders;
Verifikasi
Verifikasi relasinya cross_data menggunakan DUMP operator seperti yang ditunjukkan di bawah ini.
grunt> Dump cross_data;
Keluaran
Ini akan menghasilkan keluaran berikut, menampilkan isi relasi cross_data.
(7,Muffy,24,Indore,10000,103,2008-05-20 00:00:00,4,2060)
(7,Muffy,24,Indore,10000,101,2009-11-20 00:00:00,2,1560)
(7,Muffy,24,Indore,10000,100,2009-10-08 00:00:00,3,1500)
(7,Muffy,24,Indore,10000,102,2009-10-08 00:00:00,3,3000)
(6,Komal,22,MP,4500,103,2008-05-20 00:00:00,4,2060)
(6,Komal,22,MP,4500,101,2009-11-20 00:00:00,2,1560)
(6,Komal,22,MP,4500,100,2009-10-08 00:00:00,3,1500)
(6,Komal,22,MP,4500,102,2009-10-08 00:00:00,3,3000)
(5,Hardik,27,Bhopal,8500,103,2008-05-20 00:00:00,4,2060)
(5,Hardik,27,Bhopal,8500,101,2009-11-20 00:00:00,2,1560)
(5,Hardik,27,Bhopal,8500,100,2009-10-08 00:00:00,3,1500)
(5,Hardik,27,Bhopal,8500,102,2009-10-08 00:00:00,3,3000)
(4,Chaitali,25,Mumbai,6500,103,2008-05-20 00:00:00,4,2060)
(4,Chaitali,25,Mumbai,6500,101,2009-20 00:00:00,4,2060)
(2,Khilan,25,Delhi,1500,101,2009-11-20 00:00:00,2,1560)
(2,Khilan,25,Delhi,1500,100,2009-10-08 00:00:00,3,1500)
(2,Khilan,25,Delhi,1500,102,2009-10-08 00:00:00,3,3000)
(1,Ramesh,32,Ahmedabad,2000,103,2008-05-20 00:00:00,4,2060)
(1,Ramesh,32,Ahmedabad,2000,101,2009-11-20 00:00:00,2,1560)
(1,Ramesh,32,Ahmedabad,2000,100,2009-10-08 00:00:00,3,1500)
(1,Ramesh,32,Ahmedabad,2000,102,2009-10-08 00:00:00,3,3000)-11-20 00:00:00,2,1560)
(4,Chaitali,25,Mumbai,6500,100,2009-10-08 00:00:00,3,1500)
(4,Chaitali,25,Mumbai,6500,102,2009-10-08 00:00:00,3,3000)
(3,kaushik,23,Kota,2000,103,2008-05-20 00:00:00,4,2060)
(3,kaushik,23,Kota,2000,101,2009-11-20 00:00:00,2,1560)
(3,kaushik,23,Kota,2000,100,2009-10-08 00:00:00,3,1500)
(3,kaushik,23,Kota,2000,102,2009-10-08 00:00:00,3,3000)
(2,Khilan,25,Delhi,1500,103,2008-05-20 00:00:00,4,2060)
(2,Khilan,25,Delhi,1500,101,2009-11-20 00:00:00,2,1560)
(2,Khilan,25,Delhi,1500,100,2009-10-08 00:00:00,3,1500)
(2,Khilan,25,Delhi,1500,102,2009-10-08 00:00:00,3,3000)
(1,Ramesh,32,Ahmedabad,2000,103,2008-05-20 00:00:00,4,2060)
(1,Ramesh,32,Ahmedabad,2000,101,2009-11-20 00:00:00,2,1560)
(1,Ramesh,32,Ahmedabad,2000,100,2009-10-08 00:00:00,3,1500)
(1,Ramesh,32,Ahmedabad,2000,102,2009-10-08 00:00:00,3,3000)