Webpagebytes CMS is designed to be able to keep the content in any datastore. A CMS resource like a site page, page module or a file will keep the same identifier no matter the datastore.
A local deployment can have the datastore as an in memory H2 database and the files storage as a local directory, a cloud deployment of the same application can have the datastore as Amazon RDS and the files storage as Amazon S3 .
The CMS Import/Export functionality allows to port a web application from a deployment to another and preserve the same content.
This can be done by keeping the same identifiers of the internal resources. These identifiers are named 'External Keys' and their format are GUIDs.
External keys are used to link the Webpagebytes CMS internal resources so that these can generate complex content.