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From "Santhosh Srinivasan (JIRA)" <j...@apache.org>
Subject [jira] Commented: (PIG-1014) Pig should convert COUNT(relation) to COUNT_STAR(relation) so that all records are counted without considering nullness of the fields in the records
Date Wed, 14 Oct 2009 02:11:31 GMT

    [ https://issues.apache.org/jira/browse/PIG-1014?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12765357#action_12765357
] 

Santhosh Srinivasan commented on PIG-1014:
------------------------------------------

After a discussion with Pradeep who also graciously ran SQL queries to verify semantics, we
have the following proposal:

The semantics of COUNT could be defined as:

1. COUNT( A ) is equivalent to COUNT( A.* ) and the result of COUNT( A ) will count null tuples
in the relation
2. COUNT( A.$0) will not count null tuples in the relation

3. COUNT(A.($0, $1)) is equivalent to COUNT( A1.* ) where A1 is the relation containing tuples
with two columns and will exhibit the behavior of statement 1

OR 

3. COUNT(A.($0, $1)) is equivalent to COUNT( A1.* ) where A1 is the relation containing tuples
with two columns and will exhibit the behavior of statement 2

Point 3 needs more discussion.

Comments/thoughts/suggestions/anything else welcome.


> Pig should convert COUNT(relation) to COUNT_STAR(relation) so that all records are counted
without considering nullness of the fields in the records
> ----------------------------------------------------------------------------------------------------------------------------------------------------
>
>                 Key: PIG-1014
>                 URL: https://issues.apache.org/jira/browse/PIG-1014
>             Project: Pig
>          Issue Type: Bug
>    Affects Versions: 0.4.0
>            Reporter: Pradeep Kamath
>


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