Chapter 2 • Synchronizing at a Glance

➤An incremental synchronization does not handle deleted records. In addition, it can cause data consistency issues. For example, consistency issues could arise if the Synchronizer tries to update a record but is unable to do so for some reason, such as the record being locked in the endpoint. In such a case, the Synchronizer updates the time stamp for the link even though the records have not been synchronized. In future synchronizations, the Synchronizer will not detect that these records still need to be synchronized. To handle deleted records and data consistency issues, you can run a full synchronization. For more information, see “Full Synchronizations” on page 42.

Full Synchronizations

You can run a full synchronization to perform a full comparison of the records in each endpoint. This is useful if you want to handle records that were deleted from one of the endpoints, or if you want to synchronize records that were not synchronized in an incremental synchronization.

In a full synchronization, the Synchronizer requests from each endpoint a list of all the records in that endpoint, not just those created or modified since the previous synchronization task. It then compares this list of records with the list of records included in the identity mapping table. If a record appears in the identity mapping table but no longer appears in the endpoint, the Synchronizer infers that the record was deleted from the endpoint and deals with this case according to the options specified in the link’s configuration.

If a record appears in both the endpoint and the identity mapping table for the link, the Synchronizer synchronizes the record based on the link’s time stamp, the record’s version, and the cycle redundancy checks, as it would in an incremental synchronization. However, some records may be synchronized that would not otherwise be synchronized in an incremental synchronization. This is because in a full synchronization, all records are requested from each endpoint, and not just those modified since the previous synchronization task.

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