Neither Net Express or Visual COBOL provide a database that can be used in a production environment. The technology in these products allow you to use embedded SQL to access any vendors database that provide a compatible ODBC, ADO or JDBC driver. So you could use a low-end database such as Access or SQL Server Express in production if it fit your requirements. Using OpenESQL in this manner really allows you to access any database with the only requirement on the client machine being the appropriate ODBC, ADO or JDBC driver installed and configured with a connection string.
Alternatively we also provide access to Oracle and DB2 thru the use of 3rd party preprocessors but this would require that the end users system be configured with the appropriate Oracle or DB2 client software which requires more expertise than an average user would have.