The Oracle DRM to EBS integration is one of the most widely used programs to maintain and refresh master data easily. The EBS concurrent program pulls the data from DRM and refreshes the existing values and hierarchies with the new information. There's a specific list of attributes which demands constant special attention for every integration, they are as below:
Understanding how the data flows from DRM to EBS is useful and helps troubleshooting various scenarios quickly. Once the concurrent program Load Segment Values and Hierarchies completes fine, the values are updated and inserted in FND_FLEX_VALUES, i.e. loading is done in upsert mode. The table FND_FLEX_VALUE_NORM_HIERARCHY is truncated and loaded for that specific segment, rest data stays as-is.
The below diagram will explain schematically how the data flows, focussed mainly on the hierarchy tables in EBS. The interface tables which are truncated and loaded are GL_DRM_SEGVALUES_INTERFACE and GL_DRM_HIERARCHY_INTERFACE in the GL schema. The FND tables in APPS or APPLSYS schemas are refreshed after that.
For all the details regarding the integration, please refer the Oracle documentation.