hbase-user mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From Ted Yu <yuzhih...@gmail.com>
Subject Re: Is it possible to implement a NOT filter in Hbase?
Date Mon, 02 Jan 2017 21:31:58 GMT
bq. the cell/value that was originally skip is not return

Can you be a bit more specific (with a concrete example) : the skipped cell
would not be returned (as indicated by the ReturnCode).

Thanks

On Mon, Jan 2, 2017 at 1:06 PM, Carl M <soloninguno@hotmail.com> wrote:

> Hi Ted,
>
>
> I tried your suggestion, unfortunately it doesn't work as expected. I
> don't fully understand FilterList, but if a cell value was skip and I
> reverse the ReturnCode, i get the right row but the cell/value that was
> originally skip is not return.
>
> I also tried reversing only filterRow() method of FilterList, but I got
> the same behaviour (the original cell/value missing).
>
>
> Best,
>
>
> ________________________________
> De: Ted Yu <yuzhihong@gmail.com>
> Enviado: viernes, 30 de diciembre de 2016 12:56 p.m.
> Para: user@hbase.apache.org
> Asunto: Re: Is it possible to implement a NOT filter in Hbase?
>
> I think the ReturnCode opposite INCLUDE_AND_NEXT_COL is NEXT_COL : you're
> not interested in any version of the current Cell.
>
> Cheers
>
> On Fri, Dec 30, 2016 at 4:53 AM, Carl M <soloninguno@hotmail.com> wrote:
>
> > Thanks Ted! Great idea replacing the value in filterKeyValue. Although
> I'm
> > not quite sure looking at FilterList code if only INCLUDE/SKIP should be
> > replaced, and which should be the correct replacement for
> > INCLUDE_AND_NEXT_COL. What do you think? If not maybe i should try to
> > implement DeMorgan's law but I think it would be harder.
> >
> >
> > Best,
> >
> > ________________________________
> > De: Ted Yu <yuzhihong@gmail.com>
> > Enviado: jueves, 29 de diciembre de 2016 06:10 p.m.
> > Para: user@hbase.apache.org
> > Asunto: Re: Is it possible to implement a NOT filter in Hbase?
> >
> > You can try negating the ReturnCode from filterKeyValue() (at the root of
> > FilterList):
> >
> >   abstract public ReturnCode filterKeyValue(final Cell v) throws
> > IOException;
> >
> > INCLUDE -> SKIP
> >
> > SKIP -> INCLUDE
> >
> > Alternatively, you can use De Morgan's law to transfer the condition:
> >
> >  NOT (a = '123' AND b = '456') becomes
> >
> >  (NOT a = '123') OR (b = '456')
> >
> > On Thu, Dec 29, 2016 at 12:56 PM, Carl M <soloninguno@hotmail.com>
> wrote:
> >
> > > Hi guys
> > >
> > >
> > > I'm trying to implement some kind of NOT filter in Hbase, but don't
> know
> > > if possible, I'm playing with FilterIfMissing and FilterList.Operator
> but
> > > without luck.
> > >
> > >
> > > I know how to return rows not having a specific column, but I mean
> > > something like returning rows NOT fullfilling a condition, where
> > condition
> > > could be not only a SingleColumnValueFilter but a combined condition
> with
> > > FilterList. In SQL would be something like this for example
> > >
> > >
> > > SELECT * FROM table WHERE NOT (a = '123' AND b = '456');
> > >
> > >
> > > Thanks in advance,
> > >
> >
>

Mime
  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message