launchpad-dev team mailing list archive

[Robert Collins <robert.collins@xxxxxxxxxxxxx>]

So I made some time today, and I've got most of a rewritten
BatchNavigator that will let us use indexable DB constraints rather
than  large OFFSET values to navigate batches. This has come up in
previous performance centric mails on this list, and Jeroen had a
really clear description of the semantic problems we have with
batching that he presented during the Epic - this work should go a
fair way towards addressing both of those things (at the cost of some
fuzziness around what 'page 3' actually means).

The core grungy is roughly done, I have 'merely' integration glue - to
make sure that the existing URL's wont break and that the generation
of URLs adjacent to the current batch is done cheaply (e.g. without
materialising the adjacent batches).

I'll skip the details for now, as its not done and is subject to
change without notice, but the code is at
lp:~lifeless/lazr.batchnavigator/keyoffset if you're interested in
playing around.

Cheers,
Rob