Hmm I think it looks like it would only work if you know the previous page.
And LIMIT/OFFSET goes beyond paging I guess, and at the point where we
evaluate the query, we don't know anything about any previous pages.

I think it's bad luck on this one ... Doesn't seem like HBase supports
something equivalent to OFFSET as defined in SQL.


2014-06-23 9:42 GMT+02:00 Tomasz Guziałek <
[email protected]>:

> There is a possibility to set a start and end row to a Scan, but we need
> to know the value of the starting row, not its order as specified in OFFSET
> clause. However, I found this response on StackOverflow:
> http://stackoverflow.com/questions/23452700/hbase-scan-with-offset .
> Looks a little like a workaround, need to think if we want to incorporate
> that kind of solution in MetaModel.
>
> Regards,
> Tomasz
>
> -----Original Message-----
> From: Kasper Sørensen [mailto:[email protected]]
> Sent: Sunday, June 22, 2014 20:08
> To: [email protected]
> Subject: Re: HBase LIMIT and OFFSET.
>
> Hi Tomasz,
>
> That's right. It basically means that you functionally also have support
> for OFFSET, but it's a naive/greedy implementation which does the
> offsetting at the client side.
>
> I am not aware of a method to push down the offset criteria to the HBase
> query (scan), but if there is a way it would be an awesome improvement to
> use it. Maybe worth a little research, maybe even asking around on the
> HBase mailing lists?
>
> Kasper
>
>
> 2014-06-21 11:11 GMT+02:00 Tomasz Guziałek <
> [email protected]>:
>
> > Hello
> >
> > I need to effectively read a range of records from HBase, so I have
> > been analyzing the code for support of LIMIT and OFFSET clauses in
> > HBaseDataContext. It seems like some efforts already has been done;
> > HBaseDataContext has an implementation of materializeMainSchemaTable
> > method with setting maxRows. Do I understand it well that LIMIT is
> > supported, but not OFFSET?
> > Best regards,
> > Tomasz
> >
>

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