[openstack-dev] [oslo.db] Marker based paging

Jay Pipes jaypipes at gmail.com
Tue Nov 4 07:07:08 UTC 2014

On 11/04/2014 01:08 AM, Heald, Mike wrote:
> Thanks for that, Steven :)
> So just to clarify, results are ordered by the relevant timestamps to
> ensure consistent order and so that new records would never show on
> previous "pages" and be missed, and we're limited to just a "next
> page" navigation, and we cannot order the entire result set on any
> column but the timestamps, as this would break the paging because we
> can't do the comparisons we need to if the results aren't in that
> order. Have I got that correct?

No, that's not correct. There's nothing limiting one from ordering on 
other columns than timestamp. We always ensure that there is a secondary 
order on a column with unique values (like the primary key), in order to 
ensure that pages of results are strictly ordered even when the sort 
field is non-unique (like timestamp).

We're limited to next-previous pagination by choice because of the 
scalability and performance limitations of a limit-offset pagination 


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