In legacy versions of the SmartUI, historical data was retrieved through the datalog agent which has limitations in the amount of data it can furnish and we also have the negative effect on the agent server by getting large volumes of data this way.
The advanced datalog mechanism in the SmartUI bypasses the agent server and retrieves the data from the LGD (and LGB) files directly which is faster and allows for much larger volumes of data to be retrieved.
This functionality is enabled through the “UseAdvancedDatalogging” setting in the config for the SmartUI Server and Service (it is enabled by default in current release versions of 8 and 10)
The problem encountered here is that this functionality does not work at all if running under a timed license (aka in demo mode).
The problem manifests when a user attempts to set the trend time period longer than the datalog period.
E.g. If I have a datalog configured for 7 days but try to set the trend period to 8 days then the user will see NO historical data at all.
Reducing the trend period to 6 days for example will work correctly again.
This functionality works fully and correctly when running with a valid license.