Thanks for following through William!
D
On Wed, Jun 8, 2011 at 1:56 PM, William Oberman
<ober...@civicscience.com> wrote:
> Just in case this ends up as someone else's answer someday, here is the
> working query on real data:
> rows = LOAD 'cassandra://civicscience/observations' USING
> CassandraStorage();
> filter_rows = FILTER rows BY $1 is not null;
> counts = FOREACH filter_rows GENERATE COUNT($1);
> counts_in_bag = GROUP counts ALL;
> sum_of_bag = FOREACH counts_in_bag GENERATE SUM($1);
> dump sum_of_bag;
>
> For some reason typing the bag was causing me problems.
>
> On Tue, Jun 7, 2011 at 4:58 PM, William Oberman
> <ober...@civicscience.com>wrote:
>
>> I think FILTER will do the trick? E.g.
>>
>>
>> rows = LOAD 'cassandra://MyKeyspace/MyColumnFamily' USING
>> CassandraStorage() AS (key, columns: bag {T: tuple(name, value)});
>> filter_rows = FILTER rows BY columns is not null;
>> counts = FOREACH filter_rows GENERATE COUNT(columns);
>>
>> counts_in_bag = GROUP counts ALL;
>> sum_of_bag = FOREACH counts_in_bag GENERATE SUM($1);
>> dump sum_of_bag;
>>
>>
>> On Tue, Jun 7, 2011 at 4:33 PM, William Oberman
>> <ober...@civicscience.com>wrote:
>>
>>> 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 <ober...@civicscience.com
>>> > wrote:
>>>
>>>> That is exactly what I wanted, thanks for the confirm!
>>>>
>>>>
>>>> On Fri, Jun 3, 2011 at 4:06 PM, Dmitriy Ryaboy <dvrya...@gmail.com>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
>>>>> <ober...@civicscience.com> 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) ober...@civicscience.com
>>>>
>>>
>>>
>>>
>>> --
>>> Will Oberman
>>> Civic Science, Inc.
>>> 3030 Penn Avenue., First Floor
>>> Pittsburgh, PA 15201
>>> (M) 412-480-7835
>>> (E) ober...@civicscience.com
>>>
>>
>>
>>
>> --
>> Will Oberman
>> Civic Science, Inc.
>> 3030 Penn Avenue., First Floor
>> Pittsburgh, PA 15201
>> (M) 412-480-7835
>> (E) ober...@civicscience.com
>>
>
>
>
> --
> Will Oberman
> Civic Science, Inc.
> 3030 Penn Avenue., First Floor
> Pittsburgh, PA 15201
> (M) 412-480-7835
> (E) ober...@civicscience.com
>
