1. A method for managing object to relational one-to-many mapping for an object model mapped to a relational database, the method comprising steps of: obtaining, for a source object having a primary key value and being manipulated in a corresponding source table of the relational database, mapping meta-data including information of a corresponding target table for storing at least one target object with which the source object has a one-to-many relationship of privately owned type and information of a foreign key of the corresponding target table; generating an instruction to manipulate the at least one target object in the corresponding target table based on the mapping meta-data; and manipulating the at least one target object in the database by executing the instruction on the database.