pig tutorial - apache pig tutorial - Apache Pig - Order By - pig latin - apache pig - pig hadoop




What is ORDER BY operator in Apache Pig ?

  • The ORDER BY operator is used to display the contents of a relation in a sorted order based on one or more fields. (or) ORDER BY operator is used to sort the data in ascending or descending order, based on one or more columns.
  • Some data sort the results in an ascending order by default.
  • ORDER BY instruction:
    • Sorts relations by a specific criteria
    learn apache pig - apache pig tutorial - pig tutorial - apache pig examples - big data - apache pig script - apache pig program - apache pig download - apache pig example  - apache pig order by operation

    Syntax

    grunt> Relation_name2 = ORDER Relation_name1 BY (ASC|DESC);
    

    Example

    • Ensure that we have a file named wikitechy_employee_details.txt in the HDFS directory /pig_data/ as given below.

    Wikitechy_employee_details.txt

    111,Anu,Shankar,23,9876543210,Chennai
    112,Barvathi,Nambiayar,24,9876543211,Chennai
    113,Kajal,Nayak,24,9876543212,Trivendram
    114,Preethi,Antony,21,9876543213,Pune
    115,Raj,Gopal,21,9876543214,Hyderabad
    116,Yashika,Kannan,22,9876543215,Delhi
    117,siddu,Narayanan,22,9876543216,Kolkata
    118,Timple,Mohanthy,23,9876543217,Bhuwaneshwar
    
    • And we have loaded this file into Pig with the relation name wikitechy_student_details as shown below.
    grunt> student_details = LOAD 'hdfs://localhost:9000/pig_data/student_details.txt' USING PigStorage(',')
       as (id:int, firstname:chararray, lastname:chararray,age:int, phone:chararray, city:chararray);
    
    • Here sort the relation in a descending order based on the age of the employee and store it into another relation named order_by_data using the ORDER BY operator as given below.
    grunt> order_by_data = ORDER wikitechy_employee_details BY age DESC;
    

    Verification:

    • Now verify the relation order_by_data using the DUMP operator as given below.
    grunt> Dump order_by_data; 
    

    Output

    • The following output, display the contents of the relation order_by_data.
    113,Kajal,Nayak,24,9876543212,Trivendram
    112,Barvathi,Nambiayar,24,9876543211,Chennai
    118,Timple,Mohanthy,23,9876543217,Bhuwaneshwar
    
    111,Anu,Shankar,23,9876543210,Chennai
    117,siddu,Narayanan,22,9876543216,Kolkata
    116,Yashika,Kannan,22,9876543215,Delhi
    115,Raj,Gopal,21,9876543214,Hyderabad
    114,Preethi,Antony,21,9876543213,Pune
    

    Related Searches to Apache Pig - Order By

    Adblocker detected! Please consider reading this notice.

    We've detected that you are using AdBlock Plus or some other adblocking software which is preventing the page from fully loading.

    We don't have any banner, Flash, animation, obnoxious sound, or popup ad. We do not implement these annoying types of ads!

    We need money to operate the site, and almost all of it comes from our online advertising.

    Please add wikitechy.com to your ad blocking whitelist or disable your adblocking software.

    ×