How can I setup something so that the user has access to only child and not parent records? I can use apex to create sharing or config.Suppose user1 has access to Account and wanted to restrict on contact/oppertunity records. so that these child records are not visible to user1.User2 has access to contact/opportunity but don't want to provide access Account record.I am using customobjects and Master/detail relationship already exists and cant change it. so looking for options.Please let me know if there is a workaround.