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From Daniel Dai <jiany...@yahoo-inc.com>
Subject Re: Easy question...difference between this::form and this.form?
Date Mon, 06 Dec 2010 18:55:48 GMT
After join, cross, foreach flatten, Pig will automatically add 
"base_alias::" prefix. All other cases use "."

Daniel

Jonathan Coveney wrote:
> It's very hard to search for this among the docs because it's so generic, so
> I thought I'd ask... I'm sure the answer is painfully easy.
>
> Taking a look at this code that I found online, for example
>
> --
> -- Read in a bag of tuples (timeseries for this example) and divide the
> -- numeric column by its maximum.
> --
> %default DATABAG 'data/timeseries.tsv'
>
> data       = LOAD '$DATABAG' AS (month:chararray, count:int);
> accumulate = GROUP data ALL;
> calc_max   = FOREACH accumulate GENERATE FLATTEN(data),
> MAX(data.count) AS max_count;
> normalize  = FOREACH calc_max GENERATE data::month AS month,
> data::count AS count, (float)data::count / (float)max_count AS
> normed_count;
> DUMP normalize;
>
> What purpose does data::month serve versus data.count?
>
> Thanks
>   


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