Sql-server – SQLCMD does not print Rows affected in log file

This isn't an answer for SQLCMD specifically (I don't know of an option to discard results), but an option for testing the performance of a query and ignoring the network overhead or client-side rendering is to use the free SentryOne Plan Explorer. By design we drop the results at the server and don't bring them across, allowing you to focus on the actual performance on the query rather than the performance of your network or the power of your desktop.

The -b parameter applies to the batch, not statements within the script. If you separate each statement with a GO batch terminator, you will get the behavior you expect.

Remember that SQLCMD sends the entire batch of statements at once to SQL Server for execution. You'll need T-SQL control flow statements (including TRY/CATCH) to handle errors on the server side, if needed.