Having gotten a number of questions about Teradata’s acquisition of Xkoto, I leaned on Teradata for an update, and eventually connected with Scott Gnau. Takeaways included:

• Teradata is discontinuing Xkoto’s existing product Gridscale, which Scott characterized as being too OLTP-focused to be a good fit for Teradata. Teradata hopes and expects that existing Xkoto Gridscale customers won’t renew maintenance. (I’m not sure that they’ll even get the option to do so.)
• The point of Teradata’s technology + engineers acquisition of Xkoto is to enhance Teradata’s active-active or multi-active data warehousing capabilities, which it has had in some form for several years.
• In particular, Teradata wants to tie together different products in the Teradata product line. (Note: Those typically all run pretty much the same Teradata database management software, except insofar as they might be on different releases.)
• Scott rattled off all the plausible areas of enhancement, with multiple phrasings – performance, manageability, ease of use, tools, features, etc.
• Teradata plans to have one or two releases based on Xkoto technology in 2011.

Frankly, I’m disappointed at the struggles of clustering efforts such as Xkoto Gridscale or Continuent’s pre-Tungsten products, but if the DBMS vendors meet the same needs themselves, that’s OK too.

The logic behind active-active database implementations actually seems pretty compelling: 

• You may well be keeping a second copy of your database for high availability/hot standby.
• You might even be keeping a third copy for off-site disaster recovery.
• In some cases, you might have reasons beyond disaster recovery to distribute a database around the world.
• So why not allow queries to be run against all the copies?
• And by the way, splitting the workload up a bit by kinds (e.g., long-running vs. short query) might let you optimize the implementation of each copy of the database. (This last point becomes even more important with the rise of solid-state memory.)

Analytic DBMS vendors pretty much all need to offer this. (Possible exception: If they have a data-mart-only positioning so extreme that customers will never care about any form of failover.) That said, I must confess to not having done a good job of tracking who does or doesn’t have which features in this area to date; informative comments to this post in that regard would be much appreciated!