0.0.9

Added

• Support for optional parameters in the template IRIs for REST APIs (#493).
• Support for creating CDT literals in the RML processing component (#513).
• Adding an implementation of the batch-based bind-join algorithm for SPARQL endpoints that issues the bind-join requests without blocking, handling the processing of their responses in parallel (#499).
• Adding a dedicated folder with a few relevant example queries (#514, #517).

Changed

• Change to Hydra vocabulary for the template IRIs of REST APIs in federation descriptions (#493).
• Updated request processors to use an HTTP client provider and shared connection pools (#495).
• Adding unique IDs for plans and sub-plan, and using these in the plan printers (#500).
• Some clean up in the classes for plans and for operators (#500).
• More effective implementation of executable operators that assume that at least a minimum number of input solution mappings are available to process (#502).
• Fixes and improvements related to Web API querying and the related RML functionality (#502, #513, #518, #519, #520, #522).
• Fixes of inconsistencies and minor mistakes in the vocabulary for federation descriptions (#523).
• Bug fix in the base implementation of the bind-join algorithm, which did not correctly implement bag semantics (#498).
• Bug fix in cardinality-based join reordering (#501).
• Bug fix in join cardinality estimation (#501).

0.0.8

Added

• Initial support for RML-wrapped REST endpoints as federation members (#486).
• Adding a 'numberOfSolMapsRetrievedPerReqOp' entry to the stats of bind joins (#489).

Changed

• Reimplementation of the printers for logical and for physical plans (#487).
• Bux fix: 'equals' comparison of logical and also of physical plans must take the ID of the root operator into account (#488).

0.0.7

Added

• Basis for proper management of query-planning-related information (#455, #456, #461).
• Extending the text-based plan printers to include information about expected variables at each level of the plan (#457).
• Adding the bound join algorithm from the FedX paper (#458).
• Adding basic printing of executable plans (#473).
• Adding the option to specify in the config file which logical-to-physical plan converter and which logical-to-physical operator converter should be used, including which physical operators they should consider (#481).

Changed

• Merging the logical operators tpAdd, bgpAdd, and gpAdd into just one: gpAdd; likewise for tpOptAdd, bgpOptAdd, and gpOptAdd (#454).
• Removing the old StatsPrinter in favor of the new JSON-based one (#460).
• Changing the cardinality-based join ordering heuristic to avoid cardinality requests for plans without joins (#465).
• Removing the "GreedyBasedReordering" heuristic from the default sequence of heuristics of the logical optimizer (#467).
• Upgrading the code base to version 5.5.0 of Jena (#478).
• Reorganizes completely how the federation access manager works (#480).

0.0.6

Added

• Support for multiple VALUES clauses (#417).
• Additional endpoint of the HeFQUIN service to request query processing details (#406).
• Initial GUI with query editor (#427).
• HeFQUINEngineBuilder added as a means to consolidate and simplify the creation of a HeFQUINEngine instance (#440, #441, and #448).
• ExternalIntegrationDemo added as a means to demonstrate how the HeFQUIN engine can be used directly within the Java code of other Java projects (#448).

Changed

• Improving the text-based plan printers to make the printed plans easier to look at (d83c8c2, 21020c5, 80189b7, 66d8124, #442)
• The MergeRequests heuristic does not anymore push BIND operators into requests (#433).
• Fixing and streamlining the various bind join implementations (#443 and e7ae6a9).
• Removing the explicit notion of default components from the vocabulary for describing a HeFQUINEngine configuration (#441).
• Replacing the implicit definition of the vocabulary for describing federations by an explicit one (#432).
• Refactoring of DataRetrievalResponse (#409).
• Refactoring of QueryPatternUtils (#428).
• Moving the code for federation access into a separate Maven module called hefquin-access (#450).
• Moving the code generated from the vocabularies into hefquin-vocabs, making that an actual Maven module (#450).

0.0.5

another release for testing the release process

0.0.4

first release (mainly for testing the release process)

v0.0.1-alpha

This is the version of the code base that we used for the experiments for the DMKG 2023 paper. The repo for the paper is: https://github.com/LiUSemWeb/HeFQUIN-DMKG2023-Experiments