> We currently have no plans for having the user
databases on the same
> servers as the replicated databases. Direct joins will not be
> possible, so tools will need to be modified.
This is unfortunate, and a huge step backwards from
the situation on
For example, the project I maintain on toolserver (the
enwiki WP 1.0
assessment data) has user database tables with several million rows of
data about articles, from which it needs to select the data for pages
from fixed categories on the wiki, which themselves could have a few
thousand members. The natural way to do this is to join against the
categorylinks table. Any non-join solution is going to be much, much
A key role of the toolserver setup was that it allowed
these sorts of
joins. Web hosting is cheap and data about the live wiki is already
available in non-joinable form through the API with no replag.
Even more: If Labs replication isn't bound by Toolserver
tradition, it would be *very* nice not to fragment the data
according to the different WMF clusters, plus Commons or
not, plus (separate) user databases or not, but have one
cluster where users can join as logic suggests. As Toolser-
ver merges Commons onto other clusters already, this seems
to be possible with MySQL.