Dear all,

I want to understand when to use HTable, HTablePool and HtableAdmin in Java API ?

I tried to read Hbase book, but I got confused.. So any help please?

How to insert data using Put in a HTablePool instance..?
     

On Sat, Nov 17, 2012 at 10:14 AM, Dalia Sobhy
<[EMAIL PROTECTED]> wrote:
>
> Dear all,
>
> I want to understand when to use HTable, HTablePool and HtableAdmin in Java API ?
>

HTable to access a table.

HTablePool if lots of threads in your application accessing a table or tables.

HTableAdmin when you want to run administrative functions; its API
only has admin functions as opposed to HTable which has DML

> I tried to read Hbase book, but I got confused.. So any help please?
>
> How to insert data using Put in a HTablePool instance..?
>

HTablePool returns HTables.  Use the returned HTable to do your put against.

St.Ack

Thanks Stack :D

Another Question: Whats the difference between Scan and Get??

> Date: Sat, 17 Nov 2012 11:04:18 -0800
> Subject: Re: HTablePool
> From: [EMAIL PROTECTED]
> To: [EMAIL PROTECTED]
>
> On Sat, Nov 17, 2012 at 10:14 AM, Dalia Sobhy
> <[EMAIL PROTECTED]> wrote:
> >
> > Dear all,
> >
> > I want to understand when to use HTable, HTablePool and HtableAdmin in Java API ?
> >
>
> HTable to access a table.
>
> HTablePool if lots of threads in your application accessing a table or tables.
>
> HTableAdmin when you want to run administrative functions; its API
> only has admin functions as opposed to HTable which has DML
>
> > I tried to read Hbase book, but I got confused.. So any help please?
> >
> > How to insert data using Put in a HTablePool instance..?
> >
>
> HTablePool returns HTables.  Use the returned HTable to do your put against.
>
> St.Ack
     

On Sat, Nov 17, 2012 at 12:38 PM, Dalia Sobhy
<[EMAIL PROTECTED]> wrote:
>
> Thanks Stack :D
>
> Another Question: Whats the difference between Scan and Get??
>

What do you think?
St.Ack

All Scan operations are identical to Get with the exception of
instantiation. Get works on a single roe while in Scan rather than
specifying a single row, an optional startRow and stopRow may be defined
with Scan. If rows are not specified, all the rows are iterated. I would
suggest you to go through the official book at -
http://hbase.apache.org/book.html

Regards,
    Mohammad Tariq

On Sun, Nov 18, 2012 at 2:41 AM, Stack <[EMAIL PROTECTED]> wrote:

> On Sat, Nov 17, 2012 at 12:38 PM, Dalia Sobhy
> <[EMAIL PROTECTED]> wrote:
> >
> > Thanks Stack :D
> >
> > Another Question: Whats the difference between Scan and Get??
> >
>
> What do you think?
> St.Ack
>

Dear Mohamed,

I already read Hbase book, but because it is providing alot of functions I got confused !!

So forgive me I need to ask another question..

Does Scan returns all rows and Get only one row, am I right?

Whats better using Coprocessors or Filters for aggregate functions, in case of performance wise ?
> From: [EMAIL PROTECTED]
> Date: Sun, 18 Nov 2012 02:47:15 +0530
> Subject: Re: HTablePool
> To: [EMAIL PROTECTED]
>
> All Scan operations are identical to Get with the exception of
> instantiation. Get works on a single roe while in Scan rather than
> specifying a single row, an optional startRow and stopRow may be defined
> with Scan. If rows are not specified, all the rows are iterated. I would
> suggest you to go through the official book at -
> http://hbase.apache.org/book.html
>
> Regards,
>     Mohammad Tariq
>
>
>
> On Sun, Nov 18, 2012 at 2:41 AM, Stack <[EMAIL PROTECTED]> wrote:
>
> > On Sat, Nov 17, 2012 at 12:38 PM, Dalia Sobhy
> > <[EMAIL PROTECTED]> wrote:
> > >
> > > Thanks Stack :D
> > >
> > > Another Question: Whats the difference between Scan and Get??
> > >
> >
> > What do you think?
> > St.Ack
> >
     

Hey, no need to be sorry for anything. I never wanted to sound harsh. Don't
mind. Yes you are right. Get returns only 1 row. And for your 2nd question,
it depends on what suits your particular use case best. If it allows you to
use filters efficiently then do that. Otherwise go for co-proc.

Regards,
    Mohammad Tariq

On Sun, Nov 18, 2012 at 3:18 AM, Dalia Sobhy <[EMAIL PROTECTED]>wrote:

>
>
> Dear Mohamed,
>
> I already read Hbase book, but because it is providing alot of functions I
> got confused !!
>
> So forgive me I need to ask another question..
>
> Does Scan returns all rows and Get only one row, am I right?
>
> Whats better using Coprocessors or Filters for aggregate functions, in
> case of performance wise ?
>
>
> > From: [EMAIL PROTECTED]
> > Date: Sun, 18 Nov 2012 02:47:15 +0530
> > Subject: Re: HTablePool
> > To: [EMAIL PROTECTED]
> >
> > All Scan operations are identical to Get with the exception of
> > instantiation. Get works on a single roe while in Scan rather than
> > specifying a single row, an optional startRow and stopRow may be defined
> > with Scan. If rows are not specified, all the rows are iterated. I would
> > suggest you to go through the official book at -
> > http://hbase.apache.org/book.html
> >
> > Regards,
> >     Mohammad Tariq
> >
> >
> >
> > On Sun, Nov 18, 2012 at 2:41 AM, Stack <[EMAIL PROTECTED]> wrote:
> >
> > > On Sat, Nov 17, 2012 at 12:38 PM, Dalia Sobhy
> > > <[EMAIL PROTECTED]> wrote:
> > > >
> > > > Thanks Stack :D
> > > >
> > > > Another Question: Whats the difference between Scan and Get??
> > > >
> > >
> > > What do you think?
> > > St.Ack
> > >
>
>

Dalla,

   It is always a good idea to ask questions when first jumping into HBase.
 One piece of advice I would give is to take it slow with your jobs.  Start
as simple as possible, then move to filter if you need it.  Co-proc should
be a last step as they involve intricate understanding of HBase internals
and make your cluster exponentially harder to support since there is now
custom code being injected.

On Sat, Nov 17, 2012 at 2:00 PM, Mohammad Tariq <[EMAIL PROTECTED]> wrote:

> Hey, no need to be sorry for anything. I never wanted to sound harsh. Don't
> mind. Yes you are right. Get returns only 1 row. And for your 2nd question,
> it depends on what suits your particular use case best. If it allows you to
> use filters efficiently then do that. Otherwise go for co-proc.
>
> Regards,
>     Mohammad Tariq
>
>
>
> On Sun, Nov 18, 2012 at 3:18 AM, Dalia Sobhy <[EMAIL PROTECTED]
> >wrote:
>
> >
> >
> > Dear Mohamed,
> >
> > I already read Hbase book, but because it is providing alot of functions
> I
> > got confused !!
> >
> > So forgive me I need to ask another question..
> >
> > Does Scan returns all rows and Get only one row, am I right?
> >
> > Whats better using Coprocessors or Filters for aggregate functions, in
> > case of performance wise ?
> >
> >
> > > From: [EMAIL PROTECTED]
> > > Date: Sun, 18 Nov 2012 02:47:15 +0530
> > > Subject: Re: HTablePool
> > > To: [EMAIL PROTECTED]
> > >
> > > All Scan operations are identical to Get with the exception of
> > > instantiation. Get works on a single roe while in Scan rather than
> > > specifying a single row, an optional startRow and stopRow may be
> defined
> > > with Scan. If rows are not specified, all the rows are iterated. I
> would
> > > suggest you to go through the official book at -
> > > http://hbase.apache.org/book.html
> > >
> > > Regards,
> > >     Mohammad Tariq
> > >
> > >
> > >
> > > On Sun, Nov 18, 2012 at 2:41 AM, Stack <[EMAIL PROTECTED]> wrote:
> > >
> > > > On Sat, Nov 17, 2012 at 12:38 PM, Dalia Sobhy
> > > > <[EMAIL PROTECTED]> wrote:
> > > > >
> > > > > Thanks Stack :D
> > > > >
> > > > > Another Question: Whats the difference between Scan and Get??
> > > > >
> > > >
> > > > What do you think?
> > > > St.Ack
> > > >
> >
> >
>

--
Kevin O'Dell
Customer Operations Engineer, Cloudera

I totally agree with Kevin.

Regards,
    Mohammad Tariq

On Mon, Nov 19, 2012 at 7:15 PM, Kevin O'dell <[EMAIL PROTECTED]>wrote:

> Dalla,
>
>    It is always a good idea to ask questions when first jumping into HBase.
>  One piece of advice I would give is to take it slow with your jobs.  Start
> as simple as possible, then move to filter if you need it.  Co-proc should
> be a last step as they involve intricate understanding of HBase internals
> and make your cluster exponentially harder to support since there is now
> custom code being injected.
>
> On Sat, Nov 17, 2012 at 2:00 PM, Mohammad Tariq <[EMAIL PROTECTED]>
> wrote:
>
> > Hey, no need to be sorry for anything. I never wanted to sound harsh.
> Don't
> > mind. Yes you are right. Get returns only 1 row. And for your 2nd
> question,
> > it depends on what suits your particular use case best. If it allows you
> to
> > use filters efficiently then do that. Otherwise go for co-proc.
> >
> > Regards,
> >     Mohammad Tariq
> >
> >
> >
> > On Sun, Nov 18, 2012 at 3:18 AM, Dalia Sobhy <[EMAIL PROTECTED]
> > >wrote:
> >
> > >
> > >
> > > Dear Mohamed,
> > >
> > > I already read Hbase book, but because it is providing alot of
> functions
> > I
> > > got confused !!
> > >
> > > So forgive me I need to ask another question..
> > >
> > > Does Scan returns all rows and Get only one row, am I right?
> > >
> > > Whats better using Coprocessors or Filters for aggregate functions, in
> > > case of performance wise ?
> > >
> > >
> > > > From: [EMAIL PROTECTED]
> > > > Date: Sun, 18 Nov 2012 02:47:15 +0530
> > > > Subject: Re: HTablePool
> > > > To: [EMAIL PROTECTED]
> > > >
> > > > All Scan operations are identical to Get with the exception of
> > > > instantiation. Get works on a single roe while in Scan rather than
> > > > specifying a single row, an optional startRow and stopRow may be
> > defined
> > > > with Scan. If rows are not specified, all the rows are iterated. I
> > would
> > > > suggest you to go through the official book at -
> > > > http://hbase.apache.org/book.html
> > > >
> > > > Regards,
> > > >     Mohammad Tariq
> > > >
> > > >
> > > >
> > > > On Sun, Nov 18, 2012 at 2:41 AM, Stack <[EMAIL PROTECTED]> wrote:
> > > >
> > > > > On Sat, Nov 17, 2012 at 12:38 PM, Dalia Sobhy
> > > > > <[EMAIL PROTECTED]> wrote:
> > > > > >
> > > > > > Thanks Stack :D
> > > > > >
> > > > > > Another Question: Whats the difference between Scan and Get??
> > > > > >
> > > > >
> > > > > What do you think?
> > > > > St.Ack
> > > > >
> > >
> > >
> >
>
>
>
> --
> Kevin O'Dell
> Customer Operations Engineer, Cloudera
>