On Wed, May 14, 2014 at 12:02 AM, Gilles Dubuc <[email protected]> wrote:
>
> Ops can add indexes to the EventLogging tables for us, SQL queries
> grouping by that column should pose no challenge.
>

As far as I can see, this can't be done with a simple GROUP BY: you would
need logic like "from all records with the same sequence id which have an
authorship_change field set, select the one with the latest timestamp". In
SQL dialects supporting windowed/analytical expressions this is not bad,
but in MySQL it would require some sort of self-join, I think.
_______________________________________________
Multimedia mailing list
[email protected]
https://lists.wikimedia.org/mailman/listinfo/multimedia

Reply via email to