Effective dating: links that stop being true — Good to know

• Changing granularity from instant to day on a field that already has instant-precision periods reinterprets where the boundaries fall — check the data before switching. • An overlap policy of allow means a rollup can legitimately count one record under two parents. That may be correct; make sure it is intended. • Dating a relation does not date the RECORDS. A record deleted while its link was in force is still deleted — periods describe the link, not the thing at either end.