You are viewing a plain text version of this content. The canonical link for it is here.
Posted to user@cassandra.apache.org by "Waaij, B.D. (Bram) van der" <br...@tno.nl> on 2010/03/23 14:46:11 UTC
Timestamp for versioning?
Hi there,
Is there already support for doing something with the timestamp? I would
like to use it as a versioning mechanism of the value belonging to a
certain key. When i store a column with the same key, different value
and different timestamp, would i still be able to retrieve both
versions?
Looking at the API I can not find such method, but perhaps I am missing
something as I am new to cassandra.
Best regards,
Bram
This e-mail and its contents are subject to the DISCLAIMER at http://www.tno.nl/disclaimer/email.html
Re: Timestamp for versioning?
Posted by Erik Holstad <er...@gmail.com>.
If I'm not totally mistaken the timestamp is used for conflict resolution on
the server.
Have a look at:
http://wiki.apache.org/cassandra/DataModel for more info
2010/3/23 Waaij, B.D. (Bram) van der <br...@tno.nl>
> Can you explain then to me what the purpose is of the timestamp?
>
>
> > -----Original Message-----
> > From: Jonathan Ellis [mailto:jbellis@gmail.com]
> > Sent: dinsdag 23 maart 2010 15:35
> > To: user@cassandra.apache.org
> > Subject: Re: Timestamp for versioning?
> >
> > No, we're not planning to add support for retrieving old versions.
> >
> > 2010/3/23 Waaij, B.D. (Bram) van der <br...@tno.nl>:
> > > Are there any plans to add versioning in the near future to
> > cassandra?
> > >
> > > What is the purpose of the timestamp in the current implementation?
> > >
> > > Best regards,
> > > Bram
> > >
> > > ________________________________
> > > From: 张宇 [mailto:zyxt001@gmail.com]
> > > Sent: dinsdag 23 maart 2010 14:56
> > > To: user@cassandra.apache.org
> > > Cc: Waaij, B.D. (Bram) van der
> > > Subject: Re: Timestamp for versioning?
> > >
> > > HBase supports the version through the timestamp,but Cassandra not.
> > >
> > > 2010/3/23 Waaij, B.D. (Bram) van der <br...@tno.nl>
> > >>
> > >> Hi there,
> > >>
> > >> Is there already support for doing something with the timestamp? I
> > >> would like to use it as a versioning mechanism of the
> > value belonging
> > >> to a certain key. When i store a column with the same key,
> > different
> > >> value and different timestamp, would i still be able to
> > retrieve both versions?
> > >>
> > >> Looking at the API I can not find such method, but perhaps I am
> > >> missing something as I am new to cassandra.
> > >>
> > >> Best regards,
> > >> Bram
> > >>
> > >> This e-mail and its contents are subject to the DISCLAIMER at
> > >> http://www.tno.nl/disclaimer/email.html
> > >
> > > This e-mail and its contents are subject to the DISCLAIMER at
> > > http://www.tno.nl/disclaimer/email.html
> > >
> >
> This e-mail and its contents are subject to the DISCLAIMER at
> http://www.tno.nl/disclaimer/email.html
>
--
Regards Erik
RE: Timestamp for versioning?
Posted by "Waaij, B.D. (Bram) van der" <br...@tno.nl>.
Can you explain then to me what the purpose is of the timestamp?
> -----Original Message-----
> From: Jonathan Ellis [mailto:jbellis@gmail.com]
> Sent: dinsdag 23 maart 2010 15:35
> To: user@cassandra.apache.org
> Subject: Re: Timestamp for versioning?
>
> No, we're not planning to add support for retrieving old versions.
>
> 2010/3/23 Waaij, B.D. (Bram) van der <br...@tno.nl>:
> > Are there any plans to add versioning in the near future to
> cassandra?
> >
> > What is the purpose of the timestamp in the current implementation?
> >
> > Best regards,
> > Bram
> >
> > ________________________________
> > From: 张宇 [mailto:zyxt001@gmail.com]
> > Sent: dinsdag 23 maart 2010 14:56
> > To: user@cassandra.apache.org
> > Cc: Waaij, B.D. (Bram) van der
> > Subject: Re: Timestamp for versioning?
> >
> > HBase supports the version through the timestamp,but Cassandra not.
> >
> > 2010/3/23 Waaij, B.D. (Bram) van der <br...@tno.nl>
> >>
> >> Hi there,
> >>
> >> Is there already support for doing something with the timestamp? I
> >> would like to use it as a versioning mechanism of the
> value belonging
> >> to a certain key. When i store a column with the same key,
> different
> >> value and different timestamp, would i still be able to
> retrieve both versions?
> >>
> >> Looking at the API I can not find such method, but perhaps I am
> >> missing something as I am new to cassandra.
> >>
> >> Best regards,
> >> Bram
> >>
> >> This e-mail and its contents are subject to the DISCLAIMER at
> >> http://www.tno.nl/disclaimer/email.html
> >
> > This e-mail and its contents are subject to the DISCLAIMER at
> > http://www.tno.nl/disclaimer/email.html
> >
>
This e-mail and its contents are subject to the DISCLAIMER at http://www.tno.nl/disclaimer/email.html
Re: Timestamp for versioning?
Posted by Jonathan Ellis <jb...@gmail.com>.
No, we're not planning to add support for retrieving old versions.
2010/3/23 Waaij, B.D. (Bram) van der <br...@tno.nl>:
> Are there any plans to add versioning in the near future to cassandra?
>
> What is the purpose of the timestamp in the current implementation?
>
> Best regards,
> Bram
>
> ________________________________
> From: 张宇 [mailto:zyxt001@gmail.com]
> Sent: dinsdag 23 maart 2010 14:56
> To: user@cassandra.apache.org
> Cc: Waaij, B.D. (Bram) van der
> Subject: Re: Timestamp for versioning?
>
> HBase supports the version through the timestamp,but Cassandra not.
>
> 2010/3/23 Waaij, B.D. (Bram) van der <br...@tno.nl>
>>
>> Hi there,
>>
>> Is there already support for doing something with the timestamp? I would
>> like to use it as a versioning mechanism of the value belonging to a certain
>> key. When i store a column with the same key, different value and different
>> timestamp, would i still be able to retrieve both versions?
>>
>> Looking at the API I can not find such method, but perhaps I am missing
>> something as I am new to cassandra.
>>
>> Best regards,
>> Bram
>>
>> This e-mail and its contents are subject to the DISCLAIMER at
>> http://www.tno.nl/disclaimer/email.html
>
> This e-mail and its contents are subject to the DISCLAIMER at
> http://www.tno.nl/disclaimer/email.html
>
RE: Timestamp for versioning?
Posted by "Waaij, B.D. (Bram) van der" <br...@tno.nl>.
Hi Gary,
The description of that issue says:
"Allow a ColumnFamily to be versioned via vector clocks, instead of long timestamps. Purpose: enable incr/decr; flexible conflict resolution."
That suggests it is already possible using long timestamps. Any idea's on that?
Best regards,
Bram
> -----Original Message-----
> From: Gary Dusbabek [mailto:gdusbabek@gmail.com]
> Sent: dinsdag 23 maart 2010 15:17
> To: user@cassandra.apache.org
> Subject: Re: Timestamp for versioning?
>
> Work is in progress.
> https://issues.apache.org/jira/browse/CASSANDRA-580
>
> Gary
>
> 2010/3/23 Waaij, B.D. (Bram) van der <br...@tno.nl>:
> > Are there any plans to add versioning in the near future to
> cassandra?
> >
> > What is the purpose of the timestamp in the current implementation?
> >
> > Best regards,
> > Bram
> >
> > ________________________________
> > From: 张宇 [mailto:zyxt001@gmail.com]
> > Sent: dinsdag 23 maart 2010 14:56
> > To: user@cassandra.apache.org
> > Cc: Waaij, B.D. (Bram) van der
> > Subject: Re: Timestamp for versioning?
> >
> > HBase supports the version through the timestamp,but Cassandra not.
> >
> > 2010/3/23 Waaij, B.D. (Bram) van der <br...@tno.nl>
>
This e-mail and its contents are subject to the DISCLAIMER at http://www.tno.nl/disclaimer/email.html
Re: Timestamp for versioning?
Posted by Gary Dusbabek <gd...@gmail.com>.
Work is in progress. https://issues.apache.org/jira/browse/CASSANDRA-580
Gary
2010/3/23 Waaij, B.D. (Bram) van der <br...@tno.nl>:
> Are there any plans to add versioning in the near future to cassandra?
>
> What is the purpose of the timestamp in the current implementation?
>
> Best regards,
> Bram
>
> ________________________________
> From: 张宇 [mailto:zyxt001@gmail.com]
> Sent: dinsdag 23 maart 2010 14:56
> To: user@cassandra.apache.org
> Cc: Waaij, B.D. (Bram) van der
> Subject: Re: Timestamp for versioning?
>
> HBase supports the version through the timestamp,but Cassandra not.
>
> 2010/3/23 Waaij, B.D. (Bram) van der <br...@tno.nl>
RE: Timestamp for versioning?
Posted by "Waaij, B.D. (Bram) van der" <br...@tno.nl>.
Are there any plans to add versioning in the near future to cassandra?
What is the purpose of the timestamp in the current implementation?
Best regards,
Bram
________________________________
From: 张宇 [mailto:zyxt001@gmail.com]
Sent: dinsdag 23 maart 2010 14:56
To: user@cassandra.apache.org
Cc: Waaij, B.D. (Bram) van der
Subject: Re: Timestamp for versioning?
HBase supports the version through the timestamp,but Cassandra not.
2010/3/23 Waaij, B.D. (Bram) van der <br...@tno.nl>
Hi there,
Is there already support for doing something with the timestamp? I would like to use it as a versioning mechanism of the value belonging to a certain key. When i store a column with the same key, different value and different timestamp, would i still be able to retrieve both versions?
Looking at the API I can not find such method, but perhaps I am missing something as I am new to cassandra.
Best regards,
Bram
This e-mail and its contents are subject to the DISCLAIMER at http://www.tno.nl/disclaimer/email.html
This e-mail and its contents are subject to the DISCLAIMER at http://www.tno.nl/disclaimer/email.html
Re: Timestamp for versioning?
Posted by 张宇 <zy...@gmail.com>.
HBase supports the version through the timestamp,but Cassandra not.
2010/3/23 Waaij, B.D. (Bram) van der <br...@tno.nl>
> Hi there,
>
> Is there already support for doing something with the timestamp? I would
> like to use it as a versioning mechanism of the value belonging to a certain
> key. When i store a column with the same key, different value and different
> timestamp, would i still be able to retrieve both versions?
>
> Looking at the API I can not find such method, but perhaps I am missing
> something as I am new to cassandra.
>
> Best regards,
> Bram
>
> This e-mail and its contents are subject to the DISCLAIMER at http://www.tno.nl/disclaimer/email.html
>
>