hadoop-common-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Owen O'Malley (JIRA)" <j...@apache.org>
Subject [jira] Commented: (HADOOP-732) SequenceFile's header should allow to store metadata in the form of key/value pairs
Date Tue, 21 Nov 2006 22:17:05 GMT
    [ http://issues.apache.org/jira/browse/HADOOP-732?page=comments#action_12451794 ] 
Owen O'Malley commented on HADOOP-732:

Would the meta-data key/value pairs be required to be strings? That would simplify everything.
It isn't clear what the right API for this would be.

> SequenceFile's header should allow to store metadata in the form of key/value pairs
> -----------------------------------------------------------------------------------
>                 Key: HADOOP-732
>                 URL: http://issues.apache.org/jira/browse/HADOOP-732
>             Project: Hadoop
>          Issue Type: New Feature
>            Reporter: Runping Qi
> The sequence file currently stores a fixed list of metadata attributes, such as key/value
class names, 
> compression method, etc.  To make sequence file more self descriptable, it should allow
to store a list of key/value pairs.  One particular attribute of interest is to indicate whether
the key/value classes are actually hadoop record classes, 
> if so, store the DDls for the records. This way, we may create tools to extract DDl from
a sequence file and 
> then generate necessary classes. It also make it possible to provide an interpretive
version of Hadoop record. 
> This way, even in the situation where Hadoop or the application does not have the necessary
> a sequence file of Hadoop records can be read and deserialized "interpretively".

This message is automatically generated by JIRA.
If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa
For more information on JIRA, see: http://www.atlassian.com/software/jira


View raw message