I had not heard of this project before, so I took a look. Cubrid is from South Korea and partly developed by NHN, a Korean portal/search site [1]. Apparently it's quite popular in Korea, and NHN uses it in production for a ton of servers. It's an SQL RDBMS and claims to support a large portion of MySQL's dialect.

[1] http://opensourcebuzz.technetra.com/2010/06/21/meet-cubrid-o...