Checksums and object counts are detection strategies that allow an application to detect a partial update state. Checksums can also be used to detect inconsistencies introduced by collision resolution. Both checksums and object counts require a place to store the value used for verifying a checksum or object count. This can be on a "master" object chosen from among those involved in the application-specific relationship or on a parent object under which the related objects are stored.
For checksums, applications reading the related objects verify the checksum by calculating a local result and comparing it with the stored value. If the values do not match, the replica is in a partial update state and the objects cannot be used.
For object counts, applications count the related objects (typically children of a single parent) and compare the count with the stored value. If the counts do not match, the replica is in a partial update state and the objects cannot be used.
Some important considerations: