hadoop-pig-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Daniel Dai (JIRA)" <j...@apache.org>
Subject [jira] Created: (PIG-1324) Logical Optimizer: Nested column pruning
Date Mon, 22 Mar 2010 22:57:28 GMT
Logical Optimizer: Nested column pruning
----------------------------------------

                 Key: PIG-1324
                 URL: https://issues.apache.org/jira/browse/PIG-1324
             Project: Pig
          Issue Type: New Feature
          Components: impl
    Affects Versions: 0.7.0
            Reporter: Daniel Dai
            Assignee: Daniel Dai


Currently, column pruning does not prune sub-fields inside a complex data-type. For example:

A = load '1.txt' as (a0, a1, a2);
B = group A by a0;
C = foreach B generate group, SUM(A.a1);

Currently, since we group A as a bag, and some part of the bag is used in the following statement,
so none of the fields inside A can be pruned. We shall keep track of sub-fields and figure
out a2 is not actually needed.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.


Mime
View raw message