Home | About | Sematext search-lucene.com search-hadoop.com
 Search Hadoop and all its subprojects:

Switch to Threaded View
Pig >> mail # dev >> RequiredFields contents


Copy link to this message
-
RE: RequiredFields contents
The first element in the pair is the input number. Its mostly 0 for most
operators. For multi-input operators like join and cogroup, it will
range from 0 to (n - 1) where  n is the number of inputs.

Santhosh

-----Original Message-----
From: Dmitriy Ryaboy [mailto:[EMAIL PROTECTED]]
Sent: Thursday, November 05, 2009 9:05 PM
To: [EMAIL PROTECTED]
Subject: RequiredFields contents

Hi all,

I am looking at the RequiredFields class and it has this explanation of
what getFields() returns:

    /**
     * List of fields required from the input. This includes fields that
are
     * transformed, and thus are no longer the same fields. Using the
example 'B
     * = foreach A generate $0, $2, $3, udf($1)' would produce the list
(0, 0),
     * (0, 2), (0, 3), (0, 1). Note that the order is not guaranteed.
     */
The second element of the pair is self-explanatory -- but what is the
first element in the pair?

Thanks,
-Dmitriy