Abstract: Traditionally, relational DataBase Information Retrieval (DBIR) treats the tuplclevcl relational data as retrieval objects,and join trees of tuples as the retrieval results. However,the retrieval effect of DBIR is still not ideal. To improve the retrieval effect of DBIR, the research of Object-level relational DataBase Information Retrieval (DB0IR) was proposed, and its background and the state of the art were described. Furthermore, the main ideas and research directions of DB0IR were discussed. DB0IR provides a prospective method for DBIR in the future work.

Key words: Relational database,Information retricval,Object-level retrieval