[
https://issues.apache.org/jira/browse/PIG-161?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12590519#action_12590519
]
Alan Gates commented on PIG-161:
--------------------------------
Comments on posort patch:
1) In the comparator function you provide to the sorted data bag, you are
including functionality for both user defined sort functions and standard data
type aware sorting. This forces an if statement as the first action of every
compare, yet that if will give the same answer for every compare in a given
sort. So I think this should be broken into two inner classes,
StandardSortComparator (which just handles standard sorting) and
UserDefinedSortComparator which handles wrapping POUserFunc. Then when you
instantiate the SortedDataBag you can pass the appropriate comparator.
2) How does the user provided comparator know which columns to sort on? I
don't see where that is being communicated to it.
3) Just a clarification. This operator seems appropriate only for local
operation. Are you assuming that in the MapReduce case the POSort operator
will be replaced by a POCogroup by the MapReduce compiler?
> Rework physical plan
> --------------------
>
> Key: PIG-161
> URL: https://issues.apache.org/jira/browse/PIG-161
> Project: Pig
> Issue Type: Sub-task
> Reporter: Alan Gates
> Assignee: Alan Gates
> Attachments: arithmeticOperators.patch, incr2.patch, incr3.patch,
> incr4.patch, Phy_AbsClass.patch, pogenerate.patch, pogenerate.patch,
> pogenerate.patch, posort.patch
>
>
> This bug tracks work to rework all of the physical operators as described in
> http://wiki.apache.org/pig/PigTypesFunctionalSpec
--
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.
