[ 
https://issues.apache.org/jira/browse/CRUNCH-57?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13450368#comment-13450368
 ] 

Rahul Sharma commented on CRUNCH-57:
------------------------------------

I think I am missing a point, every PCollection is written in form of 
Writable/AvroRecord on MapReduce. So that means the data that it written on MR 
has comparable implemented in it.Then why remove the min/max/sort APIs from 
PCollection. I addition to this we use a comparator in the min/max API to 
determine the result. Why force the user to have T implements comparator, we 
could convert this data into Writable and then do a comparison ?
                
> Add a length function to PCollection
> ------------------------------------
>
>                 Key: CRUNCH-57
>                 URL: https://issues.apache.org/jira/browse/CRUNCH-57
>             Project: Crunch
>          Issue Type: New Feature
>          Components: Core
>    Affects Versions: 0.3.0
>            Reporter: Kiyan Ahmadizadeh
>            Assignee: Josh Wills
>         Attachments: CRUNCH-57.patch
>
>
> Sometimes it's useful and interesting to compute the number of elements in a 
> PCollection.
>  
> For example, suppose there was an initial PCollection that was then filtered 
> into another.  If I'm interested in how many elements of the original 
> PCollection matched the filter, I'll have to write extra code to compute this.
> PCollections should have a length method that, when called, computes the 
> number of elements in the PCollection and returns the result. 

--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira

Reply via email to