The DBMS field has always focused on capturing, organizing, storing, analyzing, and retrieving structured data. Until recently, there was limited interest in extending a DBMS to also manage text, temporal, spatial, sound, image, or video data. However, the Web has clearly demonstrated the importance of these more sophisticated data types. The general problem is that as systems add capabilities, it is hard to make these additions “cleanly.” Rather, there is a tendency to do the minimum necessary to.
