Once you have setup your schema mapping and mapped the source columns to the target columns, you should press the Compare A->B (shortcut F5) button on the toolbar to compare the source with the target.
This process loads your source and target data and then runs the data comparison to work out the ADD/UPDATE/DELETE actions to make the target the same as the source.
The Compare Results are affected by the synchronisation configuration of your target connection. By default Delete is always disabled, you can Enable and Disable any of the ADD/UPDATE/DELETE actions via these settings.
The Compare will still show the comparison results however where an action is disabled the sync check box will be cleared. This is a double opt-in check, for example if EnableDelete is false and you check a row in the results for delete it still will not be deleted unless EnableDelete is set true.
The Compare Results window shows a summary of the results, from here you can view the proposed changes, choose what to sync and export the results.
Selecting one of the Change Sets (ADD/UPDATE/DELETE) from the Results View allows you to view the actual data in this change set.
By default all the changes are included, however you can uncheck the sync check box against any changes you do not want to make. Additionally from the mini-toolbar you can check all, clear all and toggle the selected rows.
Where you have UPDATE actions, Data Sync will highlight the target columns with a yellow background that are to be updated. Since Data Sync compares the Data column by column only the changed/highlighted data is sent to the target.
To apply your changes, press the Synchronise button in the mini-toolbar.
This will then display the Synchronise Data dialog, pressing Start will begin the Synchronisation process.
You can export the Compare Results to either a Excel Spreadsheet or an Xml .NET DataSet format file via the Export buttons in the mini-toolbar.