You can choose to save the database structure to a snapshot file before comparing and synchronizing the database schema. To do this, check Take a snapshot of the database before synchronization, and then  specify a snapshot file.

Below is the xml fragment generated when you choose to save the database to a snapshot file.

<RightDatabase>
  <SqlServer>DEVSRV003\SQL2019</SqlServer>
  <DatabaseName>AdventureWorks</DatabaseName>
  <TrustedConnection>true</TrustedConnection>
  <SaveToSnapshotFile>D:\QA\Idera\SqlSchema\Snapshots\AdventureWorks.snpx</SaveToSnapshotFile>
</RightDatabase>


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