Shorthand method to test whether or not a query pattern has a solution. No information is returned about the possible query solutions, just whether or not a solution exists.
a query with a
@where pattern to test
true if the query's
@where pattern matches data in the domain
Shorthand method for retrieving a single Subject and its properties by
@id, if it exists.
the properties to retrieve. If no properties are specified, all available properties of the subject will be returned.
a promise resolving to the requested Subject with the requested
undefined if not found
Returns a stream that processes all quads matching the pattern.
The optional subject.
The optional predicate.
The optional object.
The optional graph.
The resulting quad stream.
Actively reads data from the domain.
The query executes in response to either subscription to the returned
result, or calling
All results are guaranteed to derive from the current state; however since the observable results are delivered asynchronously, the current state is not guaranteed to be live in the subscriber. In order to keep this state alive during iteration (for example, to perform a consequential operation), perform the read in the scope of a read procedure.
the declarative read description