Internal variables in IBM Rational Publishing Engine (RPE) used for native filters are not computed during runtime.
"Native filter" computed by using internal variables results in no filtering being applied to the data
Internal Variables are computed when the document generation starts, by consuming their 'default value'. Hence any modification to their values attempted through the queries in the document template would have no effect on the computation of the native filter criteria that is using these variables.
Applicable to all supported environments by RPE
Resolving the problem
This is by design.
RPE calculates the URLs of static data sources when the template execution starts and not at the time the first query from that data source is used, so to control the evaluation time a Dynamic Data Source Configuration Element (DDS) must be used.
Tip: Ensure that the respective container on which filtering is to be applied is well within the scope of the DDS. For example, if the DDS is within a container, then the respective container on which filtering is to be applied must be placed within the main container (that contains the DDS).