Data Synchronization Process Overview

After you have compared data, Data Compare for SQL Server gives you an easy and convenient way to synchronize data.

You may manually specify which tables and even which records to synchronize. Use the check boxes in the first column of the data comparison document grid to include or exclude objects to synchronization.

Note that it is highly recommended to backup target database before data synchronization. The Data Synchronization wizard allows you to perform backup.

Synchronization script is divided into batches with GO commands. GO statements are inserted after DML statements and statements, setting server options. GO statements are always inserted after the end of the DML statements for any table or view. If there are too many DML statements for a table or view (more than 1000 statements or more than 1 Mb of statements), they are divided into several batches with GO statements. In such case GO statements are inserted after each 1000 statements or after each 1 Mb of statements, depending on which comes first. You can synchronize database as one single transaction. If so, all synchronization actions will be rolled back in case of error. Otherwise, all statements before GO block with error will be executed, and statements of the invalid block and after invalid block will not be executed.

If you synchronize data with different data type, you may encounter synchronization warnings. They are displayed at the Summary tab of the Data Synchronization wizard. If you have any synchronization warnings, that means that during synchronizing data you may encounter errors or data loss because of rounding, truncation, etc. For more information about synchronization warnings, read the Synchronization Warnings topic.

The Data Synchronization wizard allows you to either apply updates immediately or create an update script for the Target database and save it to a file. For more information, visit the How To: Synchronize Data topic.

Before launching the synchronization, you may view Action Plan that contains all the actions that will be performed during synchronization. The action plan represents the synchronization script structure, so it is good to analyze it before this script will be generated or executed if you have chosen to execute the script immediately. The action Plan is displayed on the Summary page of the Data Synchronization wizard.