Hi Anil, Merge table is created on reduce side. Find usages of GridReduceQueryExecutor.createMergeTable() method.
On Thu, Feb 23, 2017 at 8:08 PM, Anil <[email protected]> wrote: > Thanks Andrey. > > where are these merge temporary tables created ? on client ? i may need to > more to time to understand the internal code :) > > Thanks > > On 23 February 2017 at 20:21, Andrey Mashenkov <[email protected] > > wrote: > >> 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 >> > > -- Best regards, Andrey V. Mashenkov
