Today, data are stored in and managed by a DBMS(database management system). Relationaldatabase is the current database technique to solve the problem in the flat-file and hierarchical database model. Inthe application of GIS(geographical information system), it recurs to a mechanism i.e. so-called Spatial Databasefor arranging, analyzing and viewing spatial data. Because spatial database contains many different data formats andstructures, these complex data lead to that spatial data manipulation and process may be very complex and difficultand tend to make mistakes. In this paper, we advise a new method by using relational database to manipulate spatialdata. The scheme is to introduce the concept of RSDD (i.e., Regularly Spatial Discrete Domains), then defineconcepts about RPO (i.e., RSDD_based Primary Object) and RO (i.e., RSDD_based Object). The concept of RSDDcan solve the conflict between the infinite precision real numbers of spatial object and the finite precision numbersystems of computers.