SQL Server database components configure Microsoft SQL Server to work with Microsoft Dynamics NAV 2013.
If SQL Server is not present on the computer where you install the database components, then Setup automatically installs SQL Server Express 2012, which you can use for prototyping, developing, and testing. We recommend that you use SQL Server 2012 or SQL Server 2008 R2 in production environments.
If you are installing the CRONUS International Ltd. demonstration database, Setup will automatically install SQL Server Express 2012 if it does not find an existing NAVDEMO instance in SQL Server. So if you intend to install the CRONUS database to an existing SQL Server installation, remember to create a NAVDEMO instance in SQL Server before you run Microsoft Dynamics NAV Setup.