An nsIRDFCompositeDataSource composes individual data sources, providing
 the illusion of a single, coherent RDF graph.
[scriptable, uuid(96343820-307c-11d2-bc15-00805f912fe7)]
interface nsIRDFCompositeDataSource : nsIRDFDataSource

Attributes


 Set this value to <code>true</code> if the composite datasource
 may contains at least one datasource that has <em>negative</em>
 assertions. (This is the default.)

 Set this value to <code>false</code> if none of the datasources
 being composed contains a negative assertion. This allows the
 composite datasource to perform some query optimizations.

 By default, this value is <code>true</true>.
attribute boolean allowNegativeAssertions 
 Set to <code>true</code> if the composite datasource should
 take care to coalesce duplicate arcs when returning values from
 queries. (This is the default.)

 Set to <code>false</code> if the composite datasource shouldn't
 bother to check for duplicates. This allows the composite
 datasource to more efficiently answer queries.

 By default, this value is <code>true</code>.
attribute boolean coalesceDuplicateArcs

Methods

 Add a datasource the the composite data source.
 @param aDataSource the datasource to add to composite
void AddDataSource(in nsIRDFDataSource aDataSource) 
 Retrieve the datasources in the composite data source.
 @return an nsISimpleEnumerator that will enumerate each
 of the datasources in the composite
nsISimpleEnumerator GetDataSources() 
 Remove a datasource from the composite data source.
 @param aDataSource the datasource to remove from the composite
void RemoveDataSource(in nsIRDFDataSource aDataSource)