Pig for Beginners

Pig Scripting Language:

How to start code on pig

1) Type Pig on terminal

    $ pig

2) Then The shell is open called 'grunt' shell

    grunt>

3) Try an samle code for get text from text file in the grunt shell. One thing Pig use your HDFS for working with data so better you 1st copy your data on the HDFS and the use data:

   grunt>A = LOAD 'data.txt' USING PigStorage(',') AS (name:chararray, class:chararray, age:int);
   
 In above command LOAD is pig function which is using for load file in pig script USING is key word when we use some predefine functions of pig here we use 'PigStorage' which is use for to filter the data in terms of symbols like:

 stu1,1st,4
 stu2,2nd,3
 stu3,3rd,2

so they assigen coloums according to the data by this ',' mark. (name:chararray, class:chararray, age:int) This is an name of our field which we gona use in our code.

4) Then we have to implement our script for filter the data like .

   grunt> B = FILTER A BY age<4;

Here is FILTER is use to filter the data from the field name age.

5) Then we have to what is the out put of our script for that we use the DUMP.

  grunt> DUMP B; 

 It give The following out put .

 output:
 (stu2,2nd,3)
 (stu3,3rd,2)


For Basic Follow the Following Links:

https://cwiki.apache.org/PIG/pigtutorial.html

https://www.youtube.com/watch?v=OoFNQDpcWR0

http://www.orzota.com/pig-for-beginners/