Hi Aaron,
Thanks for the explanation, I know the performance will be varied when the
offset is a very large number, just like what has been mentioned
on CASSANDRA-261. Even if the users implement the offset on the client side,
they suffer the same issues, I just think it would be nice if
The changes in get_count() are designed to stop counts for very large rows
running out of memory as they try to hold millions of columns in memory.
So if you ask to count all the cols in a row with 1M cols, it will (by default)
read the first 1024 columns, and then the next 1024 using the last
On Fri, Sep 23, 2011 at 12:28 PM, aaron morton aa...@thelastpickle.comwrote:
Offsets have been discussed in previously. IIRC the main concerns were
either:
There is no way to reliably count to start the offset, i.e. we do not lock
the row
In the new get_count function, cassandra does the
I was wondering if it is possible to use similar way as
CASSANDRA-2894https://issues.apache.org/jira/browse/CASSANDRA-2894
to
have the slice_predict support the offset concept? With the offset, it would
be much easier to implement the paging from the client side.
Boris
On Mon, Sep 19, 2011 at
Offsets have been discussed in previously. IIRC the main concerns were either:
There is no way to reliably count to start the offset, i.e. we do not lock the
row
Or performance related in, as there is not a reliable way to skip 10,000
columns other than counting 10,000 columns. With a start
On Mon, Sep 19, 2011 at 12:40 PM, Benoit Perroud ben...@noisette.ch wrote:
The workaround for 0.7 is calling get_slice and count on client side.
It's heavier, sure, but you will then be able to set start column
accordingly.
I was afraid of that :(
Will follow that method. Thanks.
get_count() supports the same predicate as get_slice. So you can implement the
paging yourself.
Cheers
-
Aaron Morton
Freelance Cassandra Developer
@aaronmorton
http://www.thelastpickle.com
On 19/09/2011, at 8:45 PM, Tharindu Mathew wrote:
On Mon, Sep 19, 2011 at 12:40
Unfortunately no, because you don't know what the actual
last-column-counted was.
On Mon, Sep 19, 2011 at 4:25 AM, aaron morton aa...@thelastpickle.com wrote:
get_count() supports the same predicate as get_slice. So you can implement
the paging yourself.
Cheers
-
Aaron Morton
Yes, Aaron that self implemented paging is what I'm trying.
Jonathan, the last column read in the previous result fetched is the starting
column of the next iteration. The end column remains constant. This is using
slice ranges. Afaiu, that should work.
Regards,
Tharindu
Sent from my iPhone
Hi everyone,
I noticed this line in the API docs,
The method is not O(1). It takes all the columns from disk to calculate the
answer. The only benefit of the method is that you do not need to pull all
the columns over Thrift interface to count them.
Does this mean if a row has a large number of
yes.
-
Aaron Morton
Freelance Cassandra Developer
@aaronmorton
http://www.thelastpickle.com
On 19/09/2011, at 7:16 AM, Tharindu Mathew wrote:
Hi everyone,
I noticed this line in the API docs,
The method is not O(1). It takes all the columns from disk to calculate the
This is fixed in 1.0
https://issues.apache.org/jira/browse/CASSANDRA-2894
On Sun, Sep 18, 2011 at 2:16 PM, Tharindu Mathew mcclou...@gmail.comwrote:
Hi everyone,
I noticed this line in the API docs,
The method is not O(1). It takes all the columns from disk to calculate the
answer. The
Thanks Aaron and Jake for the replies.
Any chance of a possible workaround to use for Cassandra 0.7?
On Mon, Sep 19, 2011 at 3:48 AM, aaron morton aa...@thelastpickle.comwrote:
Cool
Thanks, A
-
Aaron Morton
Freelance Cassandra Developer
@aaronmorton
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