hadoop-common-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "stack (JIRA)" <j...@apache.org>
Subject [jira] Updated: (HADOOP-1531) Add RowFilter to HRegion.HScanner
Date Tue, 03 Jul 2007 06:24:05 GMT

     [ https://issues.apache.org/jira/browse/HADOOP-1531?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]

stack updated HADOOP-1531:
--------------------------

    Attachment: RowFilter-v3.patch

Hey James:

I added a couple of tests and made some minor edits (Renamed exception InvalidRowFilter to
InvalidRowFilterException, made line lengths < 80, etc).  

On RegExpRowFilter, I understand it just one possible implementation, but was wondering if
it intentional that filterAllRemaining always returns false.  Should it return true as soon
as filter method starts to return true?  And for the filter method that takes a row and column,
the implementation tests that row matches regex OR column value matches.  I was thinking the
default would be regex matches row AND column value matches.  What you think?

> Add RowFilter to HRegion.HScanner
> ---------------------------------
>
>                 Key: HADOOP-1531
>                 URL: https://issues.apache.org/jira/browse/HADOOP-1531
>             Project: Hadoop
>          Issue Type: Improvement
>          Components: contrib/hbase
>    Affects Versions: 0.14.0
>            Reporter: James Kennedy
>            Assignee: James Kennedy
>         Attachments: RowFilter-v2.patch, RowFilter-v3.patch, RowFilter.patch
>
>
> I've implemented a RowFilterInterface and a RowFilter implementation.  This is passed
to the HRegion.HScanner via HClient.openScanner() though it is an entirely optional parameter.
> HScanner applies the filter in the next() call by iterating until it encounters a row
that is not filtered by the RowFilter.  The filter applies criteria based on row keys and/or
column data values.
> Null values are little tricky since the resultSet in that loop may represent nulls as
absent columns or as DELETED_BYTES.  Nevertheless null cases are taken care of by the filter
and you can for example retrieve all rows where column X = null.
> The initial RowFilter implementation is limited in several ways:
> * Equality test only with literal values. No !=, <, >, etc. No col1 == col2. This
is a straight-up byte[] comparison.
> * Multiple column criteria are treated as an implicit conjunction, no disjunction possible.
> * row key criteria is a regular expression only
> * row key criteria is independent of column criteria. No "if rowkey.matches(A)  and col1==B"
 although the interface is created to allow for that.
> But it should be easy to write an improved RowFilterInterface implementation to take
care of most of the above without having to change code elsewhere.

-- 
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