Grokbase Groups Pig dev August 2010
FAQ
PIG shouldn't pass all input to a UDF if the UDF specify no argument
--------------------------------------------------------------------

Key: PIG-1573
URL: https://issues.apache.org/jira/browse/PIG-1573
Project: Pig
Issue Type: Bug
Affects Versions: 0.7.0
Reporter: Xuefu Zhang
Fix For: 0.9.0


Currently If in a pig script user uses a UDF with no argument, PIG backend assumes that the UDF takes all input so at run time it passes all input as a tuple to the UDF. This assumption is incorrect, causing conceptual confusions. If a UDF takes all input, it can specify a star (*) as its argument. If it specify no argument at all, then we assume that it requires no input data.

We need to differentiate no input and all input for a UDF. Thus, in case that a UDF specify no argument, backend should pass the UDF an empty tuple.

See notes in PIG-1586 for more information.



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

Search Discussions

  • Xuefu Zhang (JIRA) at Aug 26, 2010 at 5:52 pm
    [ https://issues.apache.org/jira/browse/PIG-1573?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

    Xuefu Zhang reassigned PIG-1573:
    --------------------------------

    Assignee: Xuefu Zhang
    PIG shouldn't pass all input to a UDF if the UDF specify no argument
    --------------------------------------------------------------------

    Key: PIG-1573
    URL: https://issues.apache.org/jira/browse/PIG-1573
    Project: Pig
    Issue Type: Bug
    Affects Versions: 0.7.0
    Reporter: Xuefu Zhang
    Assignee: Xuefu Zhang
    Fix For: 0.9.0


    Currently If in a pig script user uses a UDF with no argument, PIG backend assumes that the UDF takes all input so at run time it passes all input as a tuple to the UDF. This assumption is incorrect, causing conceptual confusions. If a UDF takes all input, it can specify a star (*) as its argument. If it specify no argument at all, then we assume that it requires no input data.
    We need to differentiate no input and all input for a UDF. Thus, in case that a UDF specify no argument, backend should pass the UDF an empty tuple.
    See notes in PIG-1586 for more information.
    --
    This message is automatically generated by JIRA.
    -
    You can reply to this email to add a comment to the issue online.
  • Alan Gates (JIRA) at Sep 14, 2010 at 2:08 pm
    [ https://issues.apache.org/jira/browse/PIG-1573?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

    Alan Gates reassigned PIG-1573:
    -------------------------------

    Assignee: Daniel Dai (was: Xuefu Zhang)
    PIG shouldn't pass all input to a UDF if the UDF specify no argument
    --------------------------------------------------------------------

    Key: PIG-1573
    URL: https://issues.apache.org/jira/browse/PIG-1573
    Project: Pig
    Issue Type: Bug
    Affects Versions: 0.7.0
    Reporter: Xuefu Zhang
    Assignee: Daniel Dai
    Fix For: 0.9.0


    Currently If in a pig script user uses a UDF with no argument, PIG backend assumes that the UDF takes all input so at run time it passes all input as a tuple to the UDF. This assumption is incorrect, causing conceptual confusions. If a UDF takes all input, it can specify a star (*) as its argument. If it specify no argument at all, then we assume that it requires no input data.
    We need to differentiate no input and all input for a UDF. Thus, in case that a UDF specify no argument, backend should pass the UDF an empty tuple.
    See notes in PIG-1586 for more information.
    --
    This message is automatically generated by JIRA.
    -
    You can reply to this email to add a comment to the issue online.

Related Discussions

Discussion Navigation
viewthread | post
Discussion Overview
groupdev @
categoriespig, hadoop
postedAug 26, '10 at 5:52p
activeSep 14, '10 at 2:08p
posts3
users1
websitepig.apache.org

1 user in discussion

Alan Gates (JIRA): 3 posts

People

Translate

site design / logo © 2022 Grokbase