Option for ordering columns by timestamp in CF

[Narendra Sharma <na...@gmail.com>]

Cassandra 0.7.4
Column names in my CF are of type byte[] but I want to order columns by
timestamp. What is the best way to achieve this? Does it make sense for
Cassandra to support ordering of columns by timestamp as option for a column
family irrespective of the column name type?

Thanks,
Naren

Re: Option for ordering columns by timestamp in CF

[Martin Koch <ma...@issuu.com>]

I think that would be cool.

/Martin Koch - Issuu - Senior Software Architect

On Wed, Oct 10, 2012 at 11:44 AM, Ertio Lew <er...@gmail.com> wrote:

> I think Cassandra should provide an configurable option on per column
> family basis to do columns sorting by time-stamp rather than column names.
> This would be really helpful to maintain time-sorted columns without using
> up the column name as time-stamps which might otherwise be used to store
> most relevant column names useful for retrievals. Very frequently we need
> to store data sorted in time order. Therefore I think this may be a very
> general requirement & not specific to just my use-case alone.
>
> Does it makes sense to create an issue for this ?
>
>
>
> On Fri, Mar 25, 2011 at 2:38 AM, aaron morton <aa...@thelastpickle.com>wrote:
>
>> If you mean order by the column timestamp (as passed by the client) that
>> it not possible.
>>
>> Can you use your own timestamps as the column name and store them as long
>> values ?
>>
>> Aaron
>>
>> On 25 Mar 2011, at 09:30, Narendra Sharma wrote:
>>
>> > Cassandra 0.7.4
>> > Column names in my CF are of type byte[] but I want to order columns by
>> timestamp. What is the best way to achieve this? Does it make sense for
>> Cassandra to support ordering of columns by timestamp as option for a
>> column family irrespective of the column name type?
>> >
>> > Thanks,
>> > Naren
>>
>>
>

Re: Option for ordering columns by timestamp in CF

[Ertio Lew <er...@gmail.com>]

@B Todd Burruss:
Regarding the use cases, I think they are pretty common. At least I see its
usages very frequently in my project. Lets say when the application needs
to store a timeline of bookmark activity by a user on certain items then if
I could store the activity data containing columns(with concerned item id
as column name) & get it ordered by timestamp then I could also fetch from
that row whether or not a particular item was bookmarked by user.
Ordering columns by time is a very common requirement in any application
therefore if such a mechanism is provided by cassandra, it would be really
useful & convenient to app developers.

On Sat, Oct 13, 2012 at 8:50 PM, Martin Koch <ma...@issuu.com> wrote:

> One example could be to identify when a row was last updated. For example,
> if I have a column family for storing users, the row key is a user ID and
> the columns are values for that user, e.g. natural column names would be
> "firstName", "lastName", "address", etc; column names don't naturally
> include a date here.
>
> Sorting the coulmns by timestamp and picking the last would allow me to
> know when the row was last modified. (I could manually maintain a 'last
> modified' column as well, I know, but just coming up with a use case :).
>
> /Martin Koch
>
>
> On Fri, Oct 12, 2012 at 11:39 PM, B. Todd Burruss <bt...@gmail.com>wrote:
>
>> trying to think of a use case where you would want to order by
>> timestamp, and also have unique column names for direct access.
>>
>> not really trying to challenge the use case, but you can get ordering
>> by timestamp and still maintain a "name" for the column using
>> composites. if the first component of the composite is a timestamp,
>> then you can order on it.  when retrieved you will could have a "name"
>> in the second component .. and have dupes as long as the timestamp is
>> unique (use TimeUUID)
>>
>>
>> On Fri, Oct 12, 2012 at 7:20 AM, Derek Williams <de...@fyrie.net> wrote:
>> > You probably already know this but I'm pretty sure it wouldn't be a
>> trivial
>> > change, since to efficiently lookup a column by name requires the
>> columns to
>> > be ordered by name. A separate index would be needed in order to provide
>> > lookup by column name if the row was sorted by timestamp (which is the
>> way
>> > Redis implements it's sorted set).
>> >
>> >
>> > On Fri, Oct 12, 2012 at 12:13 AM, Ertio Lew <er...@gmail.com> wrote:
>> >>
>> >> "Make column timestamps optional"- kidding me, right ?:)  I do
>> understand
>> >> that this wont be possible as then cassandra wont be able to
>> distinguish the
>> >> latest among several copies of same column. I dont mean that. I just
>> want
>> >> the while ordering the columns, Cassandra(in an optional mode per CF)
>> should
>> >> not look at column names(they will exist though but for retrieval
>> purposes
>> >> not for ordering) but instead Cassandra would order the columns by
>> looking
>> >> at the timestamp values(timestamps would exist!). So the change would
>> be
>> >> just to provide a mode in which cassandra, while ordering, uses
>> timestamps
>> >> instead of column names.
>> >>
>> >>
>> >> On Fri, Oct 12, 2012 at 2:26 AM, Tyler Hobbs <ty...@datastax.com>
>> wrote:
>> >>>
>> >>> Without thinking too deeply about it, this is basically equivalent to
>> >>> disabling timestamps for a column family and using timestamps for
>> column
>> >>> names, though in a very indirect (and potentially confusing) manner.
>>  So, if
>> >>> you want to open a ticket, I would suggest framing it as "make column
>> >>> timestamps optional".
>> >>>
>> >>>
>> >>> On Wed, Oct 10, 2012 at 4:44 AM, Ertio Lew <er...@gmail.com>
>> wrote:
>> >>>>
>> >>>> I think Cassandra should provide an configurable option on per column
>> >>>> family basis to do columns sorting by time-stamp rather than column
>> names.
>> >>>> This would be really helpful to maintain time-sorted columns without
>> using
>> >>>> up the column name as time-stamps which might otherwise be used to
>> store
>> >>>> most relevant column names useful for retrievals. Very frequently we
>> need to
>> >>>> store data sorted in time order. Therefore I think this may be a very
>> >>>> general requirement & not specific to just my use-case alone.
>> >>>>
>> >>>> Does it makes sense to create an issue for this ?
>> >>>>
>> >>>>
>> >>>>
>> >>>>
>> >>>> On Fri, Mar 25, 2011 at 2:38 AM, aaron morton <
>> aaron@thelastpickle.com>
>> >>>> wrote:
>> >>>>>
>> >>>>> If you mean order by the column timestamp (as passed by the client)
>> >>>>> that it not possible.
>> >>>>>
>> >>>>> Can you use your own timestamps as the column name and store them as
>> >>>>> long values ?
>> >>>>>
>> >>>>> Aaron
>> >>>>>
>> >>>>> On 25 Mar 2011, at 09:30, Narendra Sharma wrote:
>> >>>>>
>> >>>>> > Cassandra 0.7.4
>> >>>>> > Column names in my CF are of type byte[] but I want to order
>> columns
>> >>>>> > by timestamp. What is the best way to achieve this? Does it make
>> sense for
>> >>>>> > Cassandra to support ordering of columns by timestamp as option
>> for a column
>> >>>>> > family irrespective of the column name type?
>> >>>>> >
>> >>>>> > Thanks,
>> >>>>> > Naren
>> >>>>>
>> >>>>
>> >>>
>> >>>
>> >>>
>> >>> --
>> >>> Tyler Hobbs
>> >>> DataStax
>> >>>
>> >>
>> >
>> >
>> >
>> > --
>> > Derek Williams
>> >
>>
>
>

Re: Option for ordering columns by timestamp in CF

[Martin Koch <ma...@issuu.com>]

One example could be to identify when a row was last updated. For example,
if I have a column family for storing users, the row key is a user ID and
the columns are values for that user, e.g. natural column names would be
"firstName", "lastName", "address", etc; column names don't naturally
include a date here.

Sorting the coulmns by timestamp and picking the last would allow me to
know when the row was last modified. (I could manually maintain a 'last
modified' column as well, I know, but just coming up with a use case :).

/Martin Koch

On Fri, Oct 12, 2012 at 11:39 PM, B. Todd Burruss <bt...@gmail.com> wrote:

> trying to think of a use case where you would want to order by
> timestamp, and also have unique column names for direct access.
>
> not really trying to challenge the use case, but you can get ordering
> by timestamp and still maintain a "name" for the column using
> composites. if the first component of the composite is a timestamp,
> then you can order on it.  when retrieved you will could have a "name"
> in the second component .. and have dupes as long as the timestamp is
> unique (use TimeUUID)
>
>
> On Fri, Oct 12, 2012 at 7:20 AM, Derek Williams <de...@fyrie.net> wrote:
> > You probably already know this but I'm pretty sure it wouldn't be a
> trivial
> > change, since to efficiently lookup a column by name requires the
> columns to
> > be ordered by name. A separate index would be needed in order to provide
> > lookup by column name if the row was sorted by timestamp (which is the
> way
> > Redis implements it's sorted set).
> >
> >
> > On Fri, Oct 12, 2012 at 12:13 AM, Ertio Lew <er...@gmail.com> wrote:
> >>
> >> "Make column timestamps optional"- kidding me, right ?:)  I do
> understand
> >> that this wont be possible as then cassandra wont be able to
> distinguish the
> >> latest among several copies of same column. I dont mean that. I just
> want
> >> the while ordering the columns, Cassandra(in an optional mode per CF)
> should
> >> not look at column names(they will exist though but for retrieval
> purposes
> >> not for ordering) but instead Cassandra would order the columns by
> looking
> >> at the timestamp values(timestamps would exist!). So the change would be
> >> just to provide a mode in which cassandra, while ordering, uses
> timestamps
> >> instead of column names.
> >>
> >>
> >> On Fri, Oct 12, 2012 at 2:26 AM, Tyler Hobbs <ty...@datastax.com>
> wrote:
> >>>
> >>> Without thinking too deeply about it, this is basically equivalent to
> >>> disabling timestamps for a column family and using timestamps for
> column
> >>> names, though in a very indirect (and potentially confusing) manner.
>  So, if
> >>> you want to open a ticket, I would suggest framing it as "make column
> >>> timestamps optional".
> >>>
> >>>
> >>> On Wed, Oct 10, 2012 at 4:44 AM, Ertio Lew <er...@gmail.com> wrote:
> >>>>
> >>>> I think Cassandra should provide an configurable option on per column
> >>>> family basis to do columns sorting by time-stamp rather than column
> names.
> >>>> This would be really helpful to maintain time-sorted columns without
> using
> >>>> up the column name as time-stamps which might otherwise be used to
> store
> >>>> most relevant column names useful for retrievals. Very frequently we
> need to
> >>>> store data sorted in time order. Therefore I think this may be a very
> >>>> general requirement & not specific to just my use-case alone.
> >>>>
> >>>> Does it makes sense to create an issue for this ?
> >>>>
> >>>>
> >>>>
> >>>>
> >>>> On Fri, Mar 25, 2011 at 2:38 AM, aaron morton <
> aaron@thelastpickle.com>
> >>>> wrote:
> >>>>>
> >>>>> If you mean order by the column timestamp (as passed by the client)
> >>>>> that it not possible.
> >>>>>
> >>>>> Can you use your own timestamps as the column name and store them as
> >>>>> long values ?
> >>>>>
> >>>>> Aaron
> >>>>>
> >>>>> On 25 Mar 2011, at 09:30, Narendra Sharma wrote:
> >>>>>
> >>>>> > Cassandra 0.7.4
> >>>>> > Column names in my CF are of type byte[] but I want to order
> columns
> >>>>> > by timestamp. What is the best way to achieve this? Does it make
> sense for
> >>>>> > Cassandra to support ordering of columns by timestamp as option
> for a column
> >>>>> > family irrespective of the column name type?
> >>>>> >
> >>>>> > Thanks,
> >>>>> > Naren
> >>>>>
> >>>>
> >>>
> >>>
> >>>
> >>> --
> >>> Tyler Hobbs
> >>> DataStax
> >>>
> >>
> >
> >
> >
> > --
> > Derek Williams
> >
>

Re: Option for ordering columns by timestamp in CF

["B. Todd Burruss" <bt...@gmail.com>]

trying to think of a use case where you would want to order by
timestamp, and also have unique column names for direct access.

not really trying to challenge the use case, but you can get ordering
by timestamp and still maintain a "name" for the column using
composites. if the first component of the composite is a timestamp,
then you can order on it.  when retrieved you will could have a "name"
in the second component .. and have dupes as long as the timestamp is
unique (use TimeUUID)


On Fri, Oct 12, 2012 at 7:20 AM, Derek Williams <de...@fyrie.net> wrote:
> You probably already know this but I'm pretty sure it wouldn't be a trivial
> change, since to efficiently lookup a column by name requires the columns to
> be ordered by name. A separate index would be needed in order to provide
> lookup by column name if the row was sorted by timestamp (which is the way
> Redis implements it's sorted set).
>
>
> On Fri, Oct 12, 2012 at 12:13 AM, Ertio Lew <er...@gmail.com> wrote:
>>
>> "Make column timestamps optional"- kidding me, right ?:)  I do understand
>> that this wont be possible as then cassandra wont be able to distinguish the
>> latest among several copies of same column. I dont mean that. I just want
>> the while ordering the columns, Cassandra(in an optional mode per CF) should
>> not look at column names(they will exist though but for retrieval purposes
>> not for ordering) but instead Cassandra would order the columns by looking
>> at the timestamp values(timestamps would exist!). So the change would be
>> just to provide a mode in which cassandra, while ordering, uses timestamps
>> instead of column names.
>>
>>
>> On Fri, Oct 12, 2012 at 2:26 AM, Tyler Hobbs <ty...@datastax.com> wrote:
>>>
>>> Without thinking too deeply about it, this is basically equivalent to
>>> disabling timestamps for a column family and using timestamps for column
>>> names, though in a very indirect (and potentially confusing) manner.  So, if
>>> you want to open a ticket, I would suggest framing it as "make column
>>> timestamps optional".
>>>
>>>
>>> On Wed, Oct 10, 2012 at 4:44 AM, Ertio Lew <er...@gmail.com> wrote:
>>>>
>>>> I think Cassandra should provide an configurable option on per column
>>>> family basis to do columns sorting by time-stamp rather than column names.
>>>> This would be really helpful to maintain time-sorted columns without using
>>>> up the column name as time-stamps which might otherwise be used to store
>>>> most relevant column names useful for retrievals. Very frequently we need to
>>>> store data sorted in time order. Therefore I think this may be a very
>>>> general requirement & not specific to just my use-case alone.
>>>>
>>>> Does it makes sense to create an issue for this ?
>>>>
>>>>
>>>>
>>>>
>>>> On Fri, Mar 25, 2011 at 2:38 AM, aaron morton <aa...@thelastpickle.com>
>>>> wrote:
>>>>>
>>>>> If you mean order by the column timestamp (as passed by the client)
>>>>> that it not possible.
>>>>>
>>>>> Can you use your own timestamps as the column name and store them as
>>>>> long values ?
>>>>>
>>>>> Aaron
>>>>>
>>>>> On 25 Mar 2011, at 09:30, Narendra Sharma wrote:
>>>>>
>>>>> > Cassandra 0.7.4
>>>>> > Column names in my CF are of type byte[] but I want to order columns
>>>>> > by timestamp. What is the best way to achieve this? Does it make sense for
>>>>> > Cassandra to support ordering of columns by timestamp as option for a column
>>>>> > family irrespective of the column name type?
>>>>> >
>>>>> > Thanks,
>>>>> > Naren
>>>>>
>>>>
>>>
>>>
>>>
>>> --
>>> Tyler Hobbs
>>> DataStax
>>>
>>
>
>
>
> --
> Derek Williams
>

Re: Option for ordering columns by timestamp in CF

[Derek Williams <de...@fyrie.net>]

You probably already know this but I'm pretty sure it wouldn't be a trivial
change, since to efficiently lookup a column by name requires the columns
to be ordered by name. A separate index would be needed in order to provide
lookup by column name if the row was sorted by timestamp (which is the way
Redis implements it's sorted set).

On Fri, Oct 12, 2012 at 12:13 AM, Ertio Lew <er...@gmail.com> wrote:

> "Make column timestamps optional"- kidding me, right ?:)  I do understand
> that this wont be possible as then cassandra wont be able to distinguish
> the latest among several copies of same column. I dont mean that. I just
> want the while ordering the columns, Cassandra(in an optional mode per CF)
> should not look at column names(they will exist though but for retrieval
> purposes not for ordering) but instead Cassandra would order the columns by
> looking at the timestamp values(timestamps would exist!). So the change
> would be just to provide a mode in which cassandra, while ordering, uses
> timestamps instead of column names.
>
>
> On Fri, Oct 12, 2012 at 2:26 AM, Tyler Hobbs <ty...@datastax.com> wrote:
>
>> Without thinking too deeply about it, this is basically equivalent to
>> disabling timestamps for a column family and using timestamps for column
>> names, though in a very indirect (and potentially confusing) manner.  So,
>> if you want to open a ticket, I would suggest framing it as "make column
>> timestamps optional".
>>
>>
>> On Wed, Oct 10, 2012 at 4:44 AM, Ertio Lew <er...@gmail.com> wrote:
>>
>>> I think Cassandra should provide an configurable option on per column
>>> family basis to do columns sorting by time-stamp rather than column names.
>>> This would be really helpful to maintain time-sorted columns without using
>>> up the column name as time-stamps which might otherwise be used to store
>>> most relevant column names useful for retrievals. Very frequently we need
>>> to store data sorted in time order. Therefore I think this may be a very
>>> general requirement & not specific to just my use-case alone.
>>>
>>> Does it makes sense to create an issue for this ?
>>>
>>>
>>>
>>>
>>> On Fri, Mar 25, 2011 at 2:38 AM, aaron morton <aa...@thelastpickle.com>wrote:
>>>
>>>> If you mean order by the column timestamp (as passed by the client)
>>>> that it not possible.
>>>>
>>>> Can you use your own timestamps as the column name and store them as
>>>> long values ?
>>>>
>>>> Aaron
>>>>
>>>> On 25 Mar 2011, at 09:30, Narendra Sharma wrote:
>>>>
>>>> > Cassandra 0.7.4
>>>> > Column names in my CF are of type byte[] but I want to order columns
>>>> by timestamp. What is the best way to achieve this? Does it make sense for
>>>> Cassandra to support ordering of columns by timestamp as option for a
>>>> column family irrespective of the column name type?
>>>> >
>>>> > Thanks,
>>>> > Naren
>>>>
>>>>
>>>
>>
>>
>> --
>> Tyler Hobbs
>> DataStax <http://datastax.com/>
>>
>>
>


-- 
Derek Williams

Re: Option for ordering columns by timestamp in CF

["Hiller, Dean" <De...@nrel.gov>]

Good, I wasn't the only one confused…I was not sure at all how "make column timestamps optional" was related to your question either…..he must have been a hurry and misread the question.

From: Ertio Lew <er...@gmail.com>>
Reply-To: "user@cassandra.apache.org<ma...@cassandra.apache.org>" <us...@cassandra.apache.org>>
Date: Friday, October 12, 2012 12:13 AM
To: "user@cassandra.apache.org<ma...@cassandra.apache.org>" <us...@cassandra.apache.org>>
Subject: Re: Option for ordering columns by timestamp in CF

"Make column timestamps optional"- kidding me, right ?:)  I do understand that this wont be possible as then cassandra wont be able to distinguish the latest among several copies of same column. I dont mean that. I just want the while ordering the columns, Cassandra(in an optional mode per CF) should not look at column names(they will exist though but for retrieval purposes not for ordering) but instead Cassandra would order the columns by looking at the timestamp values(timestamps would exist!). So the change would be just to provide a mode in which cassandra, while ordering, uses timestamps instead of column names.

On Fri, Oct 12, 2012 at 2:26 AM, Tyler Hobbs <ty...@datastax.com>> wrote:
Without thinking too deeply about it, this is basically equivalent to disabling timestamps for a column family and using timestamps for column names, though in a very indirect (and potentially confusing) manner.  So, if you want to open a ticket, I would suggest framing it as "make column timestamps optional".


On Wed, Oct 10, 2012 at 4:44 AM, Ertio Lew <er...@gmail.com>> wrote:
I think Cassandra should provide an configurable option on per column family basis to do columns sorting by time-stamp rather than column names. This would be really helpful to maintain time-sorted columns without using up the column name as time-stamps which might otherwise be used to store most relevant column names useful for retrievals. Very frequently we need to store data sorted in time order. Therefore I think this may be a very general requirement & not specific to just my use-case alone.

Does it makes sense to create an issue for this ?




On Fri, Mar 25, 2011 at 2:38 AM, aaron morton <aa...@thelastpickle.com>> wrote:
If you mean order by the column timestamp (as passed by the client) that it not possible.

Can you use your own timestamps as the column name and store them as long values ?

Aaron

On 25 Mar 2011, at 09:30, Narendra Sharma wrote:

> Cassandra 0.7.4
> Column names in my CF are of type byte[] but I want to order columns by timestamp. What is the best way to achieve this? Does it make sense for Cassandra to support ordering of columns by timestamp as option for a column family irrespective of the column name type?
>
> Thanks,
> Naren





--
Tyler Hobbs
DataStax<http://datastax.com/>

Re: Option for ordering columns by timestamp in CF

[Ertio Lew <er...@gmail.com>]

"Make column timestamps optional"- kidding me, right ?:)  I do understand
that this wont be possible as then cassandra wont be able to distinguish
the latest among several copies of same column. I dont mean that. I just
want the while ordering the columns, Cassandra(in an optional mode per CF)
should not look at column names(they will exist though but for retrieval
purposes not for ordering) but instead Cassandra would order the columns by
looking at the timestamp values(timestamps would exist!). So the change
would be just to provide a mode in which cassandra, while ordering, uses
timestamps instead of column names.

On Fri, Oct 12, 2012 at 2:26 AM, Tyler Hobbs <ty...@datastax.com> wrote:

> Without thinking too deeply about it, this is basically equivalent to
> disabling timestamps for a column family and using timestamps for column
> names, though in a very indirect (and potentially confusing) manner.  So,
> if you want to open a ticket, I would suggest framing it as "make column
> timestamps optional".
>
>
> On Wed, Oct 10, 2012 at 4:44 AM, Ertio Lew <er...@gmail.com> wrote:
>
>> I think Cassandra should provide an configurable option on per column
>> family basis to do columns sorting by time-stamp rather than column names.
>> This would be really helpful to maintain time-sorted columns without using
>> up the column name as time-stamps which might otherwise be used to store
>> most relevant column names useful for retrievals. Very frequently we need
>> to store data sorted in time order. Therefore I think this may be a very
>> general requirement & not specific to just my use-case alone.
>>
>> Does it makes sense to create an issue for this ?
>>
>>
>>
>>
>> On Fri, Mar 25, 2011 at 2:38 AM, aaron morton <aa...@thelastpickle.com>wrote:
>>
>>> If you mean order by the column timestamp (as passed by the client) that
>>> it not possible.
>>>
>>> Can you use your own timestamps as the column name and store them as
>>> long values ?
>>>
>>> Aaron
>>>
>>> On 25 Mar 2011, at 09:30, Narendra Sharma wrote:
>>>
>>> > Cassandra 0.7.4
>>> > Column names in my CF are of type byte[] but I want to order columns
>>> by timestamp. What is the best way to achieve this? Does it make sense for
>>> Cassandra to support ordering of columns by timestamp as option for a
>>> column family irrespective of the column name type?
>>> >
>>> > Thanks,
>>> > Naren
>>>
>>>
>>
>
>
> --
> Tyler Hobbs
> DataStax <http://datastax.com/>
>
>

Re: Option for ordering columns by timestamp in CF

[Tyler Hobbs <ty...@datastax.com>]

Without thinking too deeply about it, this is basically equivalent to
disabling timestamps for a column family and using timestamps for column
names, though in a very indirect (and potentially confusing) manner.  So,
if you want to open a ticket, I would suggest framing it as "make column
timestamps optional".

On Wed, Oct 10, 2012 at 4:44 AM, Ertio Lew <er...@gmail.com> wrote:

> I think Cassandra should provide an configurable option on per column
> family basis to do columns sorting by time-stamp rather than column names.
> This would be really helpful to maintain time-sorted columns without using
> up the column name as time-stamps which might otherwise be used to store
> most relevant column names useful for retrievals. Very frequently we need
> to store data sorted in time order. Therefore I think this may be a very
> general requirement & not specific to just my use-case alone.
>
> Does it makes sense to create an issue for this ?
>
>
>
>
> On Fri, Mar 25, 2011 at 2:38 AM, aaron morton <aa...@thelastpickle.com>wrote:
>
>> If you mean order by the column timestamp (as passed by the client) that
>> it not possible.
>>
>> Can you use your own timestamps as the column name and store them as long
>> values ?
>>
>> Aaron
>>
>> On 25 Mar 2011, at 09:30, Narendra Sharma wrote:
>>
>> > Cassandra 0.7.4
>> > Column names in my CF are of type byte[] but I want to order columns by
>> timestamp. What is the best way to achieve this? Does it make sense for
>> Cassandra to support ordering of columns by timestamp as option for a
>> column family irrespective of the column name type?
>> >
>> > Thanks,
>> > Naren
>>
>>
>


-- 
Tyler Hobbs
DataStax <http://datastax.com/>

Re: Option for ordering columns by timestamp in CF

[Ertio Lew <er...@gmail.com>]

I think Cassandra should provide an configurable option on per column
family basis to do columns sorting by time-stamp rather than column names.
This would be really helpful to maintain time-sorted columns without using
up the column name as time-stamps which might otherwise be used to store
most relevant column names useful for retrievals. Very frequently we need
to store data sorted in time order. Therefore I think this may be a very
general requirement & not specific to just my use-case alone.

Does it makes sense to create an issue for this ?



On Fri, Mar 25, 2011 at 2:38 AM, aaron morton <aa...@thelastpickle.com>wrote:

> If you mean order by the column timestamp (as passed by the client) that
> it not possible.
>
> Can you use your own timestamps as the column name and store them as long
> values ?
>
> Aaron
>
> On 25 Mar 2011, at 09:30, Narendra Sharma wrote:
>
> > Cassandra 0.7.4
> > Column names in my CF are of type byte[] but I want to order columns by
> timestamp. What is the best way to achieve this? Does it make sense for
> Cassandra to support ordering of columns by timestamp as option for a
> column family irrespective of the column name type?
> >
> > Thanks,
> > Naren
>
>

Re: Option for ordering columns by timestamp in CF

[aaron morton <aa...@thelastpickle.com>]

If you mean order by the column timestamp (as passed by the client) that it not possible. 

Can you use your own timestamps as the column name and store them as long values ? 

Aaron

On 25 Mar 2011, at 09:30, Narendra Sharma wrote:

> Cassandra 0.7.4
> Column names in my CF are of type byte[] but I want to order columns by timestamp. What is the best way to achieve this? Does it make sense for Cassandra to support ordering of columns by timestamp as option for a column family irrespective of the column name type?
> 
> Thanks,
> Naren