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Posted to user@cassandra.apache.org by Eric Charles <er...@u-mangate.com> on 2011/03/02 10:53:53 UTC
Re: Is it possible to get list of row keys?
Hi,
I'm also facing the need to retrieve all row keys.
What do you mean with "stable" order?
From this thread, I understand paging method with RandomPartitioner will return all keys (shuffled, but missing key, no double key).
This seems to have already told, but I prefer to double-check...
Tks,
- Eric
On 23/02/2011 15:24, Daniel Lundin wrote:
> They are, however, in *stable* order, which is important.
>
> On Wed, Feb 23, 2011 at 3:20 PM, Norman Maurer<no...@apache.org> wrote:
>> yes but be aware that the keys will not in the "right order".
>>
>> Bye,
>> Norman
>>
>> 2011/2/23 Roshan Dawrani<ro...@gmail.com>:
>>> On Wed, Feb 23, 2011 at 7:17 PM, Ching-Cheng Chen
>>> <cc...@evidentsoftware.com> wrote:
>>>> Actually, if you want to get ALL keys, I believe you can still use
>>>> RangeSliceQuery with RP.
>>>> Just use setKeys("","") as first batch call.
>>>> Then use the last key from previous batch as startKey for next batch.
>>>> Beware that since startKey is inclusive, so you'd need to ignore first key
>>>> from now on.
>>>> Keep going until you finish all batches. You will know you'd need to stop
>>>> when setKeys(key_xyz,"") return you only one key.
>>> This is what I meant to suggest when I earlier said "So, if you want all,
>>> you will need to keep paging forward and collecting the keys." :-)
Re: Is it possible to get list of row keys?
Posted by Eric Charles <er...@u-mangate.com>.
OK, got it.
Tks for the explanation,
- Eric
On 2/03/2011 14:45, Ching-Cheng Chen wrote:
> Stable order mean the keys will return in some kind of ordering (not
> alphanumeric, not numeric,), just in certain order.
>
> For example, if you use setKeys("","") as first batch call and you got
> following result.
>
> keyabc
> key456
> keydsg
> key8jkg
> keyag87
> key45s
> ...
>
> Then if you call with setKeys("keydsg","") again, you will get
> following result.
>
> keydsg
> key8jkg
> keyag87
> key45s
> ...
>
> Regards,
>
> Chen
>
> www.evidentsoftware.com <http://www.evidentsoftware.com>
>
> On Wed, Mar 2, 2011 at 4:53 AM, Eric Charles
> <eric.charles@u-mangate.com <ma...@u-mangate.com>> wrote:
>
> Hi,
>
> I'm also facing the need to retrieve all row keys.
>
> What do you mean with "stable" order?
> From this thread, I understand paging method with
> RandomPartitioner will return all keys (shuffled, but missing key,
> no double key).
> This seems to have already told, but I prefer to double-check...
>
> Tks,
> - Eric
>
>
>
> On 23/02/2011 15:24, Daniel Lundin wrote:
>
> They are, however, in *stable* order, which is important.
>
> On Wed, Feb 23, 2011 at 3:20 PM, Norman
> Maurer<norman@apache.org <ma...@apache.org>> wrote:
>
> yes but be aware that the keys will not in the "right order".
>
> Bye,
> Norman
>
> 2011/2/23 Roshan Dawrani<roshandawrani@gmail.com
> <ma...@gmail.com>>:
>
> On Wed, Feb 23, 2011 at 7:17 PM, Ching-Cheng Chen
> <cchen@evidentsoftware.com
> <ma...@evidentsoftware.com>> wrote:
>
> Actually, if you want to get ALL keys, I believe
> you can still use
> RangeSliceQuery with RP.
> Just use setKeys("","") as first batch call.
> Then use the last key from previous batch as
> startKey for next batch.
> Beware that since startKey is inclusive, so you'd
> need to ignore first key
> from now on.
> Keep going until you finish all batches. You will
> know you'd need to stop
> when setKeys(key_xyz,"") return you only one key.
>
> This is what I meant to suggest when I earlier said
> "So, if you want all,
> you will need to keep paging forward and collecting
> the keys." :-)
>
>
>
Re: Is it possible to get list of row keys?
Posted by Ching-Cheng Chen <cc...@evidentsoftware.com>.
Stable order mean the keys will return in some kind of ordering (not
alphanumeric, not numeric,), just in certain order.
For example, if you use setKeys("","") as first batch call and you got
following result.
keyabc
key456
keydsg
key8jkg
keyag87
key45s
...
Then if you call with setKeys("keydsg","") again, you will get following
result.
keydsg
key8jkg
keyag87
key45s
...
Regards,
Chen
www.evidentsoftware.com
On Wed, Mar 2, 2011 at 4:53 AM, Eric Charles <er...@u-mangate.com>wrote:
> Hi,
>
> I'm also facing the need to retrieve all row keys.
>
> What do you mean with "stable" order?
> From this thread, I understand paging method with RandomPartitioner will
> return all keys (shuffled, but missing key, no double key).
> This seems to have already told, but I prefer to double-check...
>
> Tks,
> - Eric
>
>
>
> On 23/02/2011 15:24, Daniel Lundin wrote:
>
>> They are, however, in *stable* order, which is important.
>>
>> On Wed, Feb 23, 2011 at 3:20 PM, Norman Maurer<no...@apache.org> wrote:
>>
>>> yes but be aware that the keys will not in the "right order".
>>>
>>> Bye,
>>> Norman
>>>
>>> 2011/2/23 Roshan Dawrani<ro...@gmail.com>:
>>>
>>>> On Wed, Feb 23, 2011 at 7:17 PM, Ching-Cheng Chen
>>>> <cc...@evidentsoftware.com> wrote:
>>>>
>>>>> Actually, if you want to get ALL keys, I believe you can still use
>>>>> RangeSliceQuery with RP.
>>>>> Just use setKeys("","") as first batch call.
>>>>> Then use the last key from previous batch as startKey for next batch.
>>>>> Beware that since startKey is inclusive, so you'd need to ignore first
>>>>> key
>>>>> from now on.
>>>>> Keep going until you finish all batches. You will know you'd need to
>>>>> stop
>>>>> when setKeys(key_xyz,"") return you only one key.
>>>>>
>>>> This is what I meant to suggest when I earlier said "So, if you want
>>>> all,
>>>> you will need to keep paging forward and collecting the keys." :-)
>>>>
>>>
>