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From Rajeshkumar J <rajeshkumarit8...@gmail.com>
Subject Re: Flat-wide table Hbase
Date Mon, 14 Dec 2015 10:55:25 GMT
Hi,

   So as per your reply inserting second row will not update the existing
row-key and it will add as new column qualifiers to the existing row-key

Thanks

On Mon, Dec 14, 2015 at 4:13 PM, Jean-Marc Spaggiari <
jean-marc@spaggiari.org> wrote:

> Hi,
>
> When you will insert the 2nd row, HBase wil just add is after the first
> one. On the storage side it will be another key/value entry AFTER the first
> one. On the conceptual view,, it will be seen as anothe column for the same
> row (wide approach). HBase will not update the previous existing entry. I
> will create a new one for the new key/value. The 1002-xxx | url.com that
> you have insterted before will not be touched.
>
> you have to see all those key/values are totally independent. If they have
> a different column name, what you do with one will have not any impact on
> the others.
>
> JMS
>
> 2015-12-14 5:37 GMT-05:00 Rajeshkumar J <rajeshkumarit8292@gmail.com>:
>
> > Hi,
> >
> >   Thanks for your response but in your previous answer you have mentioned
> > as follows
> >
> >
> > --------------------------------------------------------------
> > 1002 | xxx | url.com  | yy:yy:yy
> > 1002 | xxx | urrl2.com | zz:zz:zz
> > 1002 | xxx | www.sample.com | xx:xx:xx
> > --------------------------------------------------------------
> > 1003 | yyy | www.url,com | xx:xx:yy
> > --------------------------------------------------------------
> >
> > "This is if 1002-xxx is your key and "url.com" is your column qualifier"
> >
> > I have input rows as follows
> >
> > 1002 | xxx | url.com  | yy:yy:yy
> > 1002 | xxx | urrl2.com | zz:zz:zz
> > 1002 | xxx | www.sample.com | xx:xx:xx
> >
> > when I insert  first row to my hbase table 1002-xxx will be inserted as
> > rowkey and url.com will be one of my column qualifier
> >
> > what happens when I try to insert next row i.e., 1002 | xxx | urrl2.com
> |
> > zz:zz:zz for this also row-key will be 1002-xxx. As far as I know when we
> > try to insert same row-key the row will be updated.
> >
> > what to do for this cases?
> >
> > Thanks
> >
> > On Mon, Dec 14, 2015 at 3:49 PM, Jean-Marc Spaggiari <
> > jean-marc@spaggiari.org> wrote:
> >
> > > Hi Rajesh,
> > >
> > > This is not a tall table. Tall will be something whereyou put your
> domain
> > > name on the key, no on the column qualifier. Putting the domain on the
> > > columns means you will have many many columns for the same key. At the
> > end,
> > > HBase always stores the key for each and every column, what ever it is
> > tall
> > > or wide.
> > >
> > > Reading 1000 rows or reading 1000 columns for HBase is exactly the same
> > > thing. The only difference is that between 1000 rows HBase might split
> > the
> > > rows into 2 regions. If you have 1000 columns, HBase will not split
> them.
> > >
> > > HBase can return a row in few milli seconds. 2 seconds for one Cell is
> a
> > > lot...
> > >
> > > HTH
> > >
> > > JMS
> > >
> > > 2015-12-14 5:14 GMT-05:00 Rajeshkumar J <rajeshkumarit8292@gmail.com>:
> > >
> > > > Hi,
> > > >
> > > >    Thanks for your response, But you are suggesting me a tall and
> > narrow
> > > > table which is not working for me right now. As my use case involves
> > > > real-time solution I need to retrieve data from hbase table within
> one
> > or
> > > > two seconds. I have tried as you suggested which may lead to 1000
> rows
> > > for
> > > > a given id which takes more than  a minute in retrieval process.
> > > >
> > > > Thanks
> > > > Rajeshkumar
> > > >
> > > > On Mon, Dec 14, 2015 at 3:29 PM, Jean-Marc Spaggiari <
> > > > jean-marc@spaggiari.org> wrote:
> > > >
> > > > > Hi,
> > > > >
> > > > > HBase is a key value sotre. So what you are pushing here will be
> > stored
> > > > as:
> > > > > 1002 | xxx | www.sample.com | xx:xx:xx
> > > > > 1003 | yyy | www.url,com | xx:xx:yy
> > > > > 1002 | xxx | url.com  | yy:yy:yy
> > > > > 1002 | xxx | urrl2.com | zz:zz:zz
> > > > >
> > > > > HOWEVER.... HBase will never split a region withing a key and keys
> > are
> > > > > always ordered. So at the end, what you will have exactly is:
> > > > >
> > > > > --------------------------------------------------------------
> > > > > 1002 | xxx | url.com  | yy:yy:yy
> > > > > 1002 | xxx | urrl2.com | zz:zz:zz
> > > > > 1002 | xxx | www.sample.com | xx:xx:xx
> > > > > --------------------------------------------------------------
> > > > > 1003 | yyy | www.url,com | xx:xx:yy
> > > > > --------------------------------------------------------------
> > > > >
> > > > > The only places where HBase will splis are marked with "-----"
> > > > >
> > > > >
> > > > > This is if 1002-xxx is your key and "url.com" is your column
> > > qualifier.
> > > > >
> > > > > HTH
> > > > >
> > > > > JMS
> > > > >
> > > > >
> > > > > 2015-12-14 3:39 GMT-05:00 Rajeshkumar J <
> rajeshkumarit8292@gmail.com
> > >:
> > > > >
> > > > > > Hi,
> > > > > >
> > > > > >    I am going to use flat-wide tables in Hbase for my usecase
> and I
> > > > have
> > > > > > some doubts regarding this.
> > > > > >
> > > > > >    1. As per my knowledge flat-wide stores one column value
as
> key
> > > and
> > > > > > others as its values in a key-value pair relationship ( correct
> me
> > > if I
> > > > > am
> > > > > > wrong).
> > > > > >
> > > > > > I am having row  as follows
> > > > > >
> > > > > > id  | name | url | time
> > > > > >
> > > > > > 1002 | xxx | www.sample.com | xx:xx:xx
> > > > > > 1003 | yyy | www.url,com | xx:xx:yy
> > > > > > 1002 | xxx | url.com  | yy:yy:yy
> > > > > > 1002 | xxx | urrl2.com | zz:zz:zz
> > > > > >
> > > > > >
> > > > > >
> > > > > > I need to store it in flat-wide table as follows
> > > > > >
> > > > > > 1002 | xxx | www.sample.com | xx:xx:xx | 1002 | xxx | url.com
 |
> > > > > yy:yy:yy
> > > > > > |
> > > > > > 1002 | xxx | urrl2.com | zz:zz:zz
> > > > > > 1003 | yyy | www.url,com | xx:xx:yy
> > > > > >
> > > > > > How to store it like this?
> > > > > > Can any on help me in this?
> > > > > >
> > > > >
> > > >
> > >
> >
>

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