Mechanism for mapping XML schemas to object-relational database systems

摘要

The present invention provides the consistent hierarchical abstractions of data. Level can be obvious in the available data maintained except hierarchical structure or be impliedly reflected. Such level is referred to as " previously existing level ". Technology described herein is used to capture previously existing level in layered structure. Previously there are level be captured after, there are the independent datas of two groups of reflection levels: external hierarchy definition and internal hierarchy definition. Level can be changed by changing each hierarchy definition. Therefore, in order to maintain the consistency of level to reflect, in response to the change made to external hierarchy definition, it is necessary to internal hierarchy definition is changed, in response to the change made to internal hierarchy definition, it is necessary to change external hierarchy definition. Described various technologies are used to maintain the consistency between two hierarchy definitions.