hbase-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "churro morales (JIRA)" <j...@apache.org>
Subject [jira] [Commented] (HBASE-14355) Scan different TimeRange for each column family
Date Mon, 26 Oct 2015 22:14:27 GMT

    [ https://issues.apache.org/jira/browse/HBASE-14355?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14975201#comment-14975201
] 

churro morales commented on HBASE-14355:
----------------------------------------

[~stack] I agree, that makes things a lot cleaner.  My original thoughts were to pass the
Store into the constructor of StoreFileScanner which ended up being pretty invasive since
we didn't have access to the store at construction time.  But parameterizing method is cleaner,
good call.  

Now that we have the Store being passed to StoreFileScanner.shouldUseScanner() we can get
rid of the SortedSet<byte[]> columns parameter to that method and just grab the columns
from the Scan's familyMap since we have knowledge about the columnFamily - which is another
added bonus.

We are definitely going to use this patch on our cluster which is running 98x and if you guys
are interested in a backport, I can provide the patches for 1.x and 98x as well. 

I'll create a new patch with the change you suggested as well as removing the "columns" parameter
from shouldUseScanner()




> Scan different TimeRange for each column family
> -----------------------------------------------
>
>                 Key: HBASE-14355
>                 URL: https://issues.apache.org/jira/browse/HBASE-14355
>             Project: HBase
>          Issue Type: New Feature
>          Components: Client, regionserver, Scanners
>            Reporter: Dave Latham
>            Assignee: churro morales
>             Fix For: 2.0.0, 1.3.0, 0.98.16
>
>         Attachments: HBASE-14355-v1.patch, HBASE-14355-v2.patch, HBASE-14355.patch
>
>
> At present the Scan API supports only table level time range. We have specific use cases
that will benefit from per column family time range. (See background discussion at https://mail-archives.apache.org/mod_mbox/hbase-user/201508.mbox/%3CCAA4mzom00ef5eoXStK0HEtxebY8mQSs61GBVGttgpASpmhQHaw@mail.gmail.com%3E)
> There are a couple of choices that would be good to validate.  First - how to update
the Scan API to support family and table level updates.  One proposal would be to add Scan.setTimeRange(byte
family, long minTime, long maxTime), then store it in a Map<byte[], TimeRange>.  When
executing the scan, if a family has a specified TimeRange, then use it, otherwise fall back
to using the table level TimeRange.  Clients using the new API against old region servers
would not get the families correctly filterd.  Old clients sending scans to new region servers
would work correctly.
> The other question is how to get StoreFileScanner.shouldUseScanner to match up the proper
family and time range.  It has the Scan available but doesn't currently have available which
family it is a part of.  One option would be to try to pass down the column family in each
constructor path.  Another would be to instead alter shouldUseScanner to pass down the specific
TimeRange to use (similar to how it currently passes down the columns to use which also appears
to be a workaround for not having the family available). 



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

Mime
View raw message