Validating Subscriptions
Replication Monitor enables you to validate subscriptions to ensure that data on the subscriber matches data on the publisher. To validate subscriptions, SQL Server can compare row counts only, row counts and binary checksum, or row count and checksum. You can right-click a publication in the left pane of Replication Monitor and choose "Validate Subscriptions..." to choose the subscriptions you wish to validate; doing so will bring up the following dialog:
After you click Validation Options, you can tell SQL Server which algorithm to use for validating the given subscription, as shown next.
The screen indicates that certain options can take a long time and generate additional load on the server, so try to validate your subscriptions during periods of low user activity. After you specify the subscription validation option, the distribution agent will report messages similar to the following for each published table:
Table ’DimAccount’ passed rowcount (811218) and checksum validation. Checksum is not compared for any text or image columns.
You can view this information on the Distributor To Subscriber History tab under Action Message.
If you use queued-updating subscriptions, SSMS also allows viewing replication conflicts. Conflicts occur if the same row is modified on the publisher and on the subscriber. A discussion of replication conflicts is beyond the scope of this article, but be aware that you can right-click a publication with queued-updating subscriptions and choose View Conflicts to resolve any replication conflicts.