Partial rollback mechanism has been widely supported by many database management systems (DBMSs). It allows a transaction to be rolled back partially, that is, only back to a certain savepoint set by the user. A partial rollback, however, makes the DBMS buffer management complicated because it requires the DBMS to restore the state of not only the database but also the buffers. There are several literature addressing such a partial rollback in a relational DBMS (RDBMS) which has page buffer only. However, to our knowledge, there exists no literature addressing it in an object-oriented/relational DBMS (OO/ORDBMS). The RDBMS partial rollback scheme cannot be applied to OO/ORDBMSs directly. The reason is that, unlike RDBMSs, many OO/ORDBMSs use dual buffer which consists of object buffer and page buffer. In this paper we thoroughly study the partial rollback schemes for OO/ORDBMSs with dual buffer. For this, we propose four different partial rollback schemes which are based on (single) p...