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

Switch to Threaded View
Pig >> mail # user >> How to create an empty alias


Copy link to this message
-
RE: How to create an empty alias

Sorry Guys,  that last mail sent by mistake.

That mail doesn't belongs here. Please ignore it

Regards
Yogesh Kumar

> From: [EMAIL PROTECTED]
> To: [EMAIL PROTECTED]
> Subject: RE: How to create an empty alias
> Date: Thu, 8 Nov 2012 00:02:43 +0530
>
>
> Just tell us what issue you are facing and what output do you want?
>
> give a demo data and tell what kind of output you want.
>
> Instead of posting query post the demo data and what outcome you do want..
>
> Regards
> Yogesh Kumar
>
> > Date: Tue, 6 Nov 2012 23:04:15 -0500
> > Subject: Re: How to create an empty alias
> > From: [EMAIL PROTECTED]
> > To: [EMAIL PROTECTED]
> >
> > Sorry, for late response. In case you still need this.
> > You can try to read from file:/dev/null
> > This should work for most formats.
> >
> > 2012/10/18 Kevin LION <[EMAIL PROTECTED]>
> >
> > > Hello,
> > >
> > > I've a script which group lot of alias and is doing some operation on it.
> > > But it can happen that I don't need one of this alias. To don't change my
> > > code, I would like to create an empty alias. How can I do that ?
> > >
> > > Actually my code is like that :
> > > A = LOAD A AS (id, a1, a2);
> > > B = LOAD A AS (id, b1, b2);
> > > C = LOAD A AS (id, c1, c2);
> > > GROUP = COGROUP A BY id, B BY id, C BY id;
> > > GROUP2 = FOREACH GROUP GENERATE TOTUPLE(A, B, C) AS ALL;
> > > OPERATION = FOREACH GROUP2 GENERATE MyUDF(ALL);
> > >
> > > And I would like to do something like that :
> > > A = LOAD A AS (id, a1, a2);
> > > B = LOAD A AS (id, b1, b2);
> > > *C = LOAD NULL AS (id, c1, c2); <- Generate an empty alias with column id,
> > > c1, c2;*
> > > GROUP = COGROUP A BY id, B BY id, C BY id;
> > > GROUP2 = FOREACH GROUP GENERATE TOTUPLE(A, B, C) AS ALL;
> > > OPERATION = FOREACH GROUP2 GENERATE MyUDF(ALL);
> > >
> > --
> > Best regards,
> >  Vitalii Tymchyshyn
>