The WellGroupMember groupId field is a foreign key pointing to the parent WellGroup. When piper loads a group's members — for example to build a trend chart or populate a report table — it queries WellGroupMember records by groupId to find all assigned wells. Changing the groupId is not supported; to move a well, delete the existing WellGroupMember and create a new one under the target group.
Technical section
Data model, API, and internals — visible to developers.