The existing database systems treat only the current information in a systematic manner. The only information is either deleted or archived and it can not be queried; if it has to be queried, the data is time stamped in an ad hoc manner. A temporal database incorporates the concept of time at the logical level of design. Our recent work cleanly generalized the existing relational approaches to temporal databases. Our new model allows an dimensional time stamps. The two dimensional case seems to be a promising building block for a futuristic general purpose database system, in which, in addition to querying the current and the past states of a databases, one may also query the errors in the past states. Thus it is a profound application of temporal databases to databases as a whole. To harness the potential of our model, it needs further study and its applications need to be consolidated. We would first strengthen the foundations of the relational and other approaches to temporal database. We will then advance the relational, object oriented and the deductive approaches to temporal databases.