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Posted to user@cassandra.apache.org by Jonathan Ellis <jb...@gmail.com> on 2010/04/12 14:31:52 UTC

Re: FW: Is there any way to enable the multiple super column names at a time?

The supercolumn parameter to ColumnParent is optional precisely so you
can do this.  http://wiki.apache.org/cassandra/API

On Mon, Apr 12, 2010 at 6:37 AM, Dop Sun <su...@dopsun.com> wrote:
> I guess I'm putting in the wrong email list. Sorry for this.
>
> My question in short is: whether I can get a certain range of super column
> in a single query?
>
> I have checked the following APIs, but looks they don't work for this:
> get: for a single column
> get_slice: contains column_parent as parameter, means a single CF + SC
> multiget_slice: contains column_parent as parameter, means a single CF + SC
> get_range_slices: contains column_parent as parameter, means a single CF +
> SC
>
> Regards,
> Dop
>
> -----Original Message-----
> From: Dop Sun [mailto:sunht@dopsun.com]
> Sent: Monday, April 12, 2010 6:41 AM
> To: dev@cassandra.apache.org
> Subject: Is there any way to enable the multiple super column names at a
> time?
>
> Hi,
>
> I don't know whether I have missed anything here, but can we get columns for
> multiple Super Column Names at a time, like what we can do for Keys (by key
> range or list of keys) or columns (by column range or column list)?
>
> While I'm doing the work with Cassandra, I usually think the structure like
> this:
>
> KS - CF - Key - Super Column - Column
>
> But looks like I should change it to something like:
>
> KS - CF - Super Column - Key - Column
>
> Since CF-SuperColumn are combined within a single parameter: ColumnParent,
> and they are usually unique (single) in a query.
>
> Regards,
> Dop
>
>
>
>
>

RE: FW: Is there any way to enable the multiple super column names at a time?

Posted by Dop Sun <su...@dopsun.com>.
Updates:

I found the reason:
The tricky is: the relationship between: predicate and column_parent:

1. If column_parent has NOT set the super_column, the SlicePredicate's start
and finish is for the super_column 
2. If column_parent has set the super_column, the SlicePredicate's start and
finish is for the standard columns

Thanks for all your help. Appreciated!

Dop

-----Original Message-----
From: Dop Sun [mailto:sunht@dopsun.com] 
Sent: Monday, April 12, 2010 9:44 PM
To: user@cassandra.apache.org
Subject: RE: FW: Is there any way to enable the multiple super column names
at a time?

Also tried:
client.multiget_slice(ksName, mKeyList, parent, predicate,
ConsistencyLevel.ONE);

Gets the same result, if I put the super_column as null or empty array, it
returns nothing, but if I give the correct super_column value, it returns
expected 3 columns.

I'm using the Keyspace1.Super1.

Regards,
Dop


-----Original Message-----
From: Dop Sun [mailto:sunht@dopsun.com] 
Sent: Monday, April 12, 2010 9:03 PM
To: user@cassandra.apache.org
Subject: RE: FW: Is there any way to enable the multiple super column names
at a time?

Thanks for your quick reply. 

Actually, I tried to leave it as null or byte[0], nothing returned, and if I
put right super column value, it returns 3 items actually (in my simple test
case).

I'm using get_range_slices.

I'm calling two times with all other arguments same.

I'm using the 0.6 rc1 via Thrift API.

Regards,
Dop

-----Original Message-----
From: Jonathan Ellis [mailto:jbellis@gmail.com] 
Sent: Monday, April 12, 2010 8:32 PM
To: user@cassandra.apache.org
Subject: Re: FW: Is there any way to enable the multiple super column names
at a time?

The supercolumn parameter to ColumnParent is optional precisely so you
can do this.  http://wiki.apache.org/cassandra/API

On Mon, Apr 12, 2010 at 6:37 AM, Dop Sun <su...@dopsun.com> wrote:
> I guess I'm putting in the wrong email list. Sorry for this.
>
> My question in short is: whether I can get a certain range of super column
> in a single query?
>
> I have checked the following APIs, but looks they don't work for this:
> get: for a single column
> get_slice: contains column_parent as parameter, means a single CF + SC
> multiget_slice: contains column_parent as parameter, means a single CF +
SC
> get_range_slices: contains column_parent as parameter, means a single CF +
> SC
>
> Regards,
> Dop
>
> -----Original Message-----
> From: Dop Sun [mailto:sunht@dopsun.com]
> Sent: Monday, April 12, 2010 6:41 AM
> To: dev@cassandra.apache.org
> Subject: Is there any way to enable the multiple super column names at a
> time?
>
> Hi,
>
> I don't know whether I have missed anything here, but can we get columns
for
> multiple Super Column Names at a time, like what we can do for Keys (by
key
> range or list of keys) or columns (by column range or column list)?
>
> While I'm doing the work with Cassandra, I usually think the structure
like
> this:
>
> KS - CF - Key - Super Column - Column
>
> But looks like I should change it to something like:
>
> KS - CF - Super Column - Key - Column
>
> Since CF-SuperColumn are combined within a single parameter: ColumnParent,
> and they are usually unique (single) in a query.
>
> Regards,
> Dop
>
>
>
>
>







RE: FW: Is there any way to enable the multiple super column names at a time?

Posted by Dop Sun <su...@dopsun.com>.
Also tried:
client.multiget_slice(ksName, mKeyList, parent, predicate,
ConsistencyLevel.ONE);

Gets the same result, if I put the super_column as null or empty array, it
returns nothing, but if I give the correct super_column value, it returns
expected 3 columns.

I'm using the Keyspace1.Super1.

Regards,
Dop


-----Original Message-----
From: Dop Sun [mailto:sunht@dopsun.com] 
Sent: Monday, April 12, 2010 9:03 PM
To: user@cassandra.apache.org
Subject: RE: FW: Is there any way to enable the multiple super column names
at a time?

Thanks for your quick reply. 

Actually, I tried to leave it as null or byte[0], nothing returned, and if I
put right super column value, it returns 3 items actually (in my simple test
case).

I'm using get_range_slices.

I'm calling two times with all other arguments same.

I'm using the 0.6 rc1 via Thrift API.

Regards,
Dop

-----Original Message-----
From: Jonathan Ellis [mailto:jbellis@gmail.com] 
Sent: Monday, April 12, 2010 8:32 PM
To: user@cassandra.apache.org
Subject: Re: FW: Is there any way to enable the multiple super column names
at a time?

The supercolumn parameter to ColumnParent is optional precisely so you
can do this.  http://wiki.apache.org/cassandra/API

On Mon, Apr 12, 2010 at 6:37 AM, Dop Sun <su...@dopsun.com> wrote:
> I guess I'm putting in the wrong email list. Sorry for this.
>
> My question in short is: whether I can get a certain range of super column
> in a single query?
>
> I have checked the following APIs, but looks they don't work for this:
> get: for a single column
> get_slice: contains column_parent as parameter, means a single CF + SC
> multiget_slice: contains column_parent as parameter, means a single CF +
SC
> get_range_slices: contains column_parent as parameter, means a single CF +
> SC
>
> Regards,
> Dop
>
> -----Original Message-----
> From: Dop Sun [mailto:sunht@dopsun.com]
> Sent: Monday, April 12, 2010 6:41 AM
> To: dev@cassandra.apache.org
> Subject: Is there any way to enable the multiple super column names at a
> time?
>
> Hi,
>
> I don't know whether I have missed anything here, but can we get columns
for
> multiple Super Column Names at a time, like what we can do for Keys (by
key
> range or list of keys) or columns (by column range or column list)?
>
> While I'm doing the work with Cassandra, I usually think the structure
like
> this:
>
> KS - CF - Key - Super Column - Column
>
> But looks like I should change it to something like:
>
> KS - CF - Super Column - Key - Column
>
> Since CF-SuperColumn are combined within a single parameter: ColumnParent,
> and they are usually unique (single) in a query.
>
> Regards,
> Dop
>
>
>
>
>





RE: FW: Is there any way to enable the multiple super column names at a time?

Posted by Dop Sun <su...@dopsun.com>.
Thanks for your quick reply. 

Actually, I tried to leave it as null or byte[0], nothing returned, and if I
put right super column value, it returns 3 items actually (in my simple test
case).

I'm using get_range_slices.

I'm calling two times with all other arguments same.

I'm using the 0.6 rc1 via Thrift API.

Regards,
Dop

-----Original Message-----
From: Jonathan Ellis [mailto:jbellis@gmail.com] 
Sent: Monday, April 12, 2010 8:32 PM
To: user@cassandra.apache.org
Subject: Re: FW: Is there any way to enable the multiple super column names
at a time?

The supercolumn parameter to ColumnParent is optional precisely so you
can do this.  http://wiki.apache.org/cassandra/API

On Mon, Apr 12, 2010 at 6:37 AM, Dop Sun <su...@dopsun.com> wrote:
> I guess I'm putting in the wrong email list. Sorry for this.
>
> My question in short is: whether I can get a certain range of super column
> in a single query?
>
> I have checked the following APIs, but looks they don't work for this:
> get: for a single column
> get_slice: contains column_parent as parameter, means a single CF + SC
> multiget_slice: contains column_parent as parameter, means a single CF +
SC
> get_range_slices: contains column_parent as parameter, means a single CF +
> SC
>
> Regards,
> Dop
>
> -----Original Message-----
> From: Dop Sun [mailto:sunht@dopsun.com]
> Sent: Monday, April 12, 2010 6:41 AM
> To: dev@cassandra.apache.org
> Subject: Is there any way to enable the multiple super column names at a
> time?
>
> Hi,
>
> I don't know whether I have missed anything here, but can we get columns
for
> multiple Super Column Names at a time, like what we can do for Keys (by
key
> range or list of keys) or columns (by column range or column list)?
>
> While I'm doing the work with Cassandra, I usually think the structure
like
> this:
>
> KS - CF - Key - Super Column - Column
>
> But looks like I should change it to something like:
>
> KS - CF - Super Column - Key - Column
>
> Since CF-SuperColumn are combined within a single parameter: ColumnParent,
> and they are usually unique (single) in a query.
>
> Regards,
> Dop
>
>
>
>
>