With carrying out my own database research wanted to find out how many database research groups exist. I have found that quite a large number of database research groups worldwide exist.
A few of the ones I have discovered are
European database research groups
The group is to increase the usefulness of database systems to users by creating, extending, and applying database technology. They are located in Redmond, Washington, which is in the greater Seattle area.
The Microsoft Jim Gray Systems Lab is a collaborative effort between Microsoft and the Computer Sciences Department at the University of Wisconsin-Madison that started in March 2008.
They have been conducting database related research for almost 30 years
Berkeley has led database systems research for over a quarter century. Their research covers new challenges in data management, as well as data-centric approaches to diverse areas including distributed systems, programming languages, statistical computation, human computing and interaction, and technology for developing regions.
The University of Washington's database group aims at broadening the focus of database and data management techniques beyond their traditional scope. They do both theoretical and systems work in areas such as probabilistic databases, stream processing, sensor-based monitoring, databases and the web, XML, data management for ubiquitous computing, data integration, and data mining.