Hi Anil,

Query initiator node will fetch all records before appling sorting. It is
known bug [1], and I hope it will be fixed soon.

What about QueryCursor, it is just wrapper that supports query
cancellation. Pagination is applied to load map-queries results by reducer
in async manner.

Looking at these classes can help you to understand how it works:
GridReduceQueryExecutor, GridMapQueryExecutor, GridMergeIndex,
GridQueryNextPageRequest, GridQueryNextPageResponse
It looks like sorting is applied by H2 internals when reducer makes query
to merge table.


[1] https://issues.apache.org/jira/browse/IGNITE-3013

On Thu, Feb 23, 2017 at 2:34 PM, Anil <[email protected]> wrote:

> Hi,
>
> QueryCursor is used to get the records in pages instead of loading all
> records into client memory.
>
> and I understand that sorting needs to get all the records into client
> (assuming reducer is client. correct me if i am wrong) memory.
>
> How does QueryCursor with sort query behaves ? Thanks.
>
> Thanks.
>



-- 
Best regards,
Andrey V. Mashenkov

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