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Re: trying to count all tuples
I tried this same script on closer to production data, and I'm getting
errors.  I'm 50% sure it's this:
https://issues.apache.org/jira/browse/PIG-1283

One of my rows in cassandra has no columns (maybe?), which maybe causes a
null bag, which causes COUNT to blow up (at least, that's my theory).  As a
workaround, can I have COUNT ignore/skip rows with null columns?  I'll start
digging through the docs as well.

will

On Fri, Jun 3, 2011 at 4:09 PM, William Oberman <[EMAIL PROTECTED]>wrote:

> That is exactly what I wanted, thanks for the confirm!
>
>
> On Fri, Jun 3, 2011 at 4:06 PM, Dmitriy Ryaboy <[EMAIL PROTECTED]> wrote:
>
>> I am not sure what you mean by "count all columns". The code you have
>> counts all *cells*.
>> So:
>> id1: col1, col2
>> id2: col1, col2, col3
>>
>> has 3 columns in a conventional sense, but your code will return 5. Is
>> that what you want? If so, your code seems correct.
>>
>> D
>>
>> On Fri, Jun 3, 2011 at 12:53 PM, William Oberman
>> <[EMAIL PROTECTED]> wrote:
>> > Howdy,
>> >
>> > I'm coming from cassandra, and I'm actually trying to count all columns
>> in a
>> > column family.  I believe that is similar to counting the number tuples
>> in a
>> > bag in the lingo in the pig manual.  It was harder than I expected, but
>> I
>> > think this works:
>> > rows = LOAD 'cassandra://MyKeyspace/MyColumnFamily' USING
>> CassandraStorage()
>> > AS (key, columns: bag {T: tuple(name, value)});
>> > counts = FOREACH rows GENERATE COUNT(columns);
>> > counts_in_bag = GROUP counts ALL;
>> > sum_of_bag = FOREACH counts_in_bag  GENERATE SUM($1);
>> > dump sum_of_bag;
>> >
>> > My question is: am I right that it works?  I started with 3 keys having
>> a
>> > total of 5 columns and got (5).  Then I added a new key/column, and
>> another
>> > column on an existing key and got (7).  So, it seems like it's working.
>> > But, was there a better way to write it?
>> >
>> > Thanks!
>> >
>> > will
>> >
>>
>
>
>
> --
> Will Oberman
> Civic Science, Inc.
> 3030 Penn Avenue., First Floor
> Pittsburgh, PA 15201
> (M) 412-480-7835
> (E) [EMAIL PROTECTED]
>

--
Will Oberman
Civic Science, Inc.
3030 Penn Avenue., First Floor
Pittsburgh, PA 15201
(M) 412-480-7835
(E) [EMAIL PROTECTED]