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From Sergey Malov <sma...@collective.com>
Subject Re: create a view on existing production table ?
Date Tue, 07 Jul 2015 13:46:30 GMT
Thanks, Anil, that’s what I thought initially. I was a bit confused with what James wrote,
that I can create a view, but it wouldn’t be feasible.
Essentially, it seems, I need to impose a strict schema on Hbase table for Phoenix to work
on it directly, which  defeats a purpose of schema-less db imho. Not complaining, I understand
that to marry SQL and non-SQL design, sacrifices should be made.

Thank you,
Sergey Malov

From: anil gupta <anilgupta84@gmail.com<mailto:anilgupta84@gmail.com>>
Reply-To: "user@phoenix.apache.org<mailto:user@phoenix.apache.org>" <user@phoenix.apache.org<mailto:user@phoenix.apache.org>>
Date: Tuesday, July 7, 2015 at 02:49
To: "user@phoenix.apache.org<mailto:user@phoenix.apache.org>" <user@phoenix.apache.org<mailto:user@phoenix.apache.org>>
Subject: Re: create a view on existing production table ?

Hi Sergey,

You **can't** create a view that would work with dynamic columns. Dynamic columns are specified
along with query(you can specify one, two or three columns, Phoenix will not complain) because
Phoenix has no idea about existence of these columns(otherwise they wont be called Dynamic
columns). Hope this clarifies further.

Thanks,
Anil Gupta

On Mon, Jul 6, 2015 at 4:05 PM, Sergey Malov <smalov@collective.com<mailto:smalov@collective.com>>
wrote:
Thanks for your replies, guys.
I’m trying to understand that dynamic column feature, not sure how to apply it in my case.
Let’s look at the concrete example : suppose I have an existing Hbase table “X", which
has only one column family “A”. Each record has either one or two or three columns with
qualifiers “A1”,”A2”, or “A3”, I.e. some records has only one column A.A1, or
A.A2, or A.A3, some just two, some all three.
How can I create a view using dynamic columns that I can query later ?

Thank you,
Sergey Malov

From: anil gupta <anilgupta84@gmail.com<mailto:anilgupta84@gmail.com>>
Reply-To: "user@phoenix.apache.org<mailto:user@phoenix.apache.org>" <user@phoenix.apache.org<mailto:user@phoenix.apache.org>>
Date: Friday, June 26, 2015 at 18:28

To: "user@phoenix.apache.org<mailto:user@phoenix.apache.org>" <user@phoenix.apache.org<mailto:user@phoenix.apache.org>>
Subject: Re: create a view on existing production table ?

Hi Sergey,

Since you have hundreds of thousand of columns. You can query your data by using dynamic columns
features of phoenix. In this way, you wont need to predefine 100's of thousands of columns.

Thanks,
Anil Gupta

On Fri, Jun 26, 2015 at 11:34 AM, James Taylor <jamestaylor@apache.org<mailto:jamestaylor@apache.org>>
wrote:
Sergey,
It is possible, but maybe in your case it's not feasible.
Thanks,
James


On Friday, June 26, 2015, Sergey Malov <smalov@collective.com<mailto:smalov@collective.com>>
wrote:
Hi James,
>From you reply I understand that it is NOT possible to create such a view, because each
family can have different number of columns, and it could be just one column per family for
one PK, and hundreds of thousands for another PK. How can I possibly accommodate it in a view
specification, if I need to explicitly define column by name  ?
Or I misunderstand something ?

Thank you,
Sergey

From: James Taylor <jamestaylor@apache.org>
Reply-To: "user@phoenix.apache.org" <user@phoenix.apache.org>
Date: Friday, June 26, 2015 at 12:04
To: "user@phoenix.apache.org" <user@phoenix.apache.org>
Subject: Re: create a view on existing production table ?

Hi Sergey,
Yes, you can create a Phoenix view over this HBase table, but you have to explicitly list
columns by name (i.e. column qualifier) either at view creation time or at read time (using
dynamic columns). Also, the row key must conform to what Phoenix expects if there are multiple
columns in your PK.
Thanks,
James

On Wednesday, June 24, 2015, Sergey Malov <smalov@collective.com> wrote:
My apologies if this info can be found somewhere, I don’t see it.
I have a production table “profile” with the following schema :


{NAME => 'edge', BLOOMFILTER => 'ROW', VERSIONS => '2', IN_MEMORY => 'false',
KEEP_DELETED_CELLS => 'false', DATA_BLOCK_ENCODING => 'FAST_DIFF', COMPRESSION =>
'SNAPPY', TTL => '

FOREVER', MIN_VERSIONS => '0', BLOCKCACHE => 'true', BLOCKSIZE => '65536', REPLICATION_SCOPE
=> '1'}

{NAME => 'export', BLOOMFILTER => 'ROW', VERSIONS => '2', IN_MEMORY => 'false',
KEEP_DELETED_CELLS => 'false', DATA_BLOCK_ENCODING => 'FAST_DIFF', COMPRESSION =>
'SNAPPY', TTL =>

 'FOREVER', MIN_VERSIONS => '0', BLOCKCACHE => 'true', BLOCKSIZE => '65536', REPLICATION_SCOPE
=> '1'}

{NAME => 'visitor', BLOOMFILTER => 'ROW', VERSIONS => '2', IN_MEMORY => 'false',
KEEP_DELETED_CELLS => 'false', DATA_BLOCK_ENCODING => 'FAST_DIFF', COMPRESSION =>
'SNAPPY', TTL =

> 'FOREVER', MIN_VERSIONS => '0', BLOCKCACHE => 'true', BLOCKSIZE => '65536',
REPLICATION_SCOPE => '1'}

Each of these families can have variable number of column for a given key, with some having
hundreds of thousands columns.
Is it possible to create a Phoenix view for such a table ?

Thank you,
Sergey Malov



--
Thanks & Regards,
Anil Gupta



--
Thanks & Regards,
Anil Gupta

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