]> Triple stores. 3 REDLAND Library Triple stores. RDF Triple stores typedef librdf_storage; typedef librdf_storage_factory; void librdf_storage_register_factory (librdf_world *world, const char *name, const char *label, void (factorylibrdf_storage_factory*) ()); int librdf_storage_enumerate (librdf_world *world, unsigned int counter, const char **name, const char **label); librdf_storage* librdf_new_storage (librdf_world *world, const char *storage_name, const char *name, const char *options_string); librdf_storage* librdf_new_storage_with_options (librdf_world *world, const char *storage_name, const char *name, librdf_hash *options); librdf_storage* librdf_new_storage_from_storage (librdf_storage *old_storage); librdf_storage* librdf_new_storage_from_factory (librdf_world *world, librdf_storage_factory *factory, const char *name, librdf_hash *options); void librdf_free_storage (librdf_storage *storage); int librdf_storage_open (librdf_storage *storage, librdf_model *model); int librdf_storage_close (librdf_storage *storage); int librdf_storage_size (librdf_storage *storage); int librdf_storage_add_statement (librdf_storage *storage, librdf_statement *statement); int librdf_storage_add_statements (librdf_storage *storage, librdf_stream *statement_stream); int librdf_storage_remove_statement (librdf_storage *storage, librdf_statement *statement); int librdf_storage_contains_statement (librdf_storage *storage, librdf_statement *statement); librdf_stream* librdf_storage_serialise (librdf_storage *storage); librdf_stream* librdf_storage_find_statements (librdf_storage *storage, librdf_statement *statement); librdf_stream* librdf_storage_find_statements_with_options (librdf_storage *storage, librdf_statement *statement, librdf_node *context_node, librdf_hash *options); librdf_iterator* librdf_storage_get_sources (librdf_storage *storage, librdf_node *arc, librdf_node *target); librdf_iterator* librdf_storage_get_arcs (librdf_storage *storage, librdf_node *source, librdf_node *target); librdf_iterator* librdf_storage_get_targets (librdf_storage *storage, librdf_node *source, librdf_node *arc); librdf_iterator* librdf_storage_get_arcs_in (librdf_storage *storage, librdf_node *node); librdf_iterator* librdf_storage_get_arcs_out (librdf_storage *storage, librdf_node *node); int librdf_storage_has_arc_in (librdf_storage *storage, librdf_node *node, librdf_node *property); int librdf_storage_has_arc_out (librdf_storage *storage, librdf_node *node, librdf_node *property); int librdf_storage_context_add_statement (librdf_storage *storage, librdf_node *context, librdf_statement *statement); int librdf_storage_context_add_statements (librdf_storage *storage, librdf_node *context, librdf_stream *stream); int librdf_storage_context_remove_statement (librdf_storage *storage, librdf_node *context, librdf_statement *statement); int librdf_storage_context_remove_statements (librdf_storage *storage, librdf_node *context); librdf_stream* librdf_storage_context_as_stream (librdf_storage *storage, librdf_node *context); librdf_stream* librdf_storage_context_serialise (librdf_storage *storage, librdf_node *context); int librdf_storage_supports_query (librdf_storage *storage, librdf_query *query); librdf_query_results* librdf_storage_query_execute (librdf_storage *storage, librdf_query *query); int librdf_storage_sync (librdf_storage *storage); librdf_stream* librdf_storage_find_statements_in_context (librdf_storage *storage, librdf_statement *statement, librdf_node *context_node); librdf_iterator* librdf_storage_get_contexts (librdf_storage *storage); librdf_node* librdf_storage_get_feature (librdf_storage *storage, librdf_uri *feature); int librdf_storage_set_feature (librdf_storage *storage, librdf_uri *feature, librdf_node *value); int librdf_storage_transaction_commit (librdf_storage *storage); void* librdf_storage_transaction_get_handle (librdf_storage *storage); int librdf_storage_transaction_rollback (librdf_storage *storage); int librdf_storage_transaction_start (librdf_storage *storage); int librdf_storage_transaction_start_with_handle (librdf_storage *storage, void *handle); void librdf_storage_add_reference (librdf_storage *storage); void librdf_storage_remove_reference (librdf_storage *storage); Provides classes to create triple stores to back the RDF graph interface (librdf_model). Most of the methods are for implementing the RDF model API and have the same name. librdf_storagetypedef struct librdf_storage_s librdf_storage; Redland storage class. librdf_storage_factorytypedef struct librdf_storage_factory_s librdf_storage_factory; Redland storage factory class. librdf_storage_register_factoryvoid librdf_storage_register_factory (librdf_world *world, const char *name, const char *label, void (factorylibrdf_storage_factory*) ()); Register a storage factory. world : redland world object name : the storage factory name label : the storage factory label factory : pointer to function to call to register the factory librdf_storage_enumerateint librdf_storage_enumerate (librdf_world *world, unsigned int counter, const char **name, const char **label); Get information on storages. world : redland world object counter : index into the list of storages name : pointer to store the name of the storage (or NULL) label : pointer to store syntax readable label (or NULL) Returns : non 0 on failure of if counter is out of range librdf_new_storagelibrdf_storage* librdf_new_storage (librdf_world *world, const char *storage_name, const char *name, const char *options_string); Constructor - create a new librdf_storage object. The options are encoded as described in librdf_hash_from_string() and can be NULL if none are required. world : redland world object storage_name : the storage factory name name : an identifier for the storage options_string : options to initialise storage Returns : a new librdf_storage object or NULL on failure librdf_new_storage_with_optionslibrdf_storage* librdf_new_storage_with_options (librdf_world *world, const char *storage_name, const char *name, librdf_hash *options); Constructor - create a new librdf_storage object. The options can be NULL if none are required. world : redland world object storage_name : the storage factory name name : an identifier for the storage options : librdf_hash of options to use Returns : a new librdf_storage object or NULL on failure librdf_new_storage_from_storagelibrdf_storage* librdf_new_storage_from_storage (librdf_storage *old_storage); Should create a new storage in the same context as the existing one as appropriate for the storage. For example, in a RDBMS storage it would be a new database, or in on disk it would be a new set of files. This will mean automatically generating a new identifier for the storage, maybe based on the existing storage identifier. old_storage : the existing storage librdf_storage to use Returns : a new librdf_storage object or NULL on failure librdf_new_storage_from_factorylibrdf_storage* librdf_new_storage_from_factory (librdf_world *world, librdf_storage_factory *factory, const char *name, librdf_hash *options); Constructor - create a new librdf_storage object. If the options are present, they become owned by the storage and should no longer be used. world : redland world object factory : the factory to use to construct the storage name : name to use for storage options : librdf_hash of options to initialise storage Returns : a new librdf_storage object or NULL on failure librdf_free_storagevoid librdf_free_storage (librdf_storage *storage); Destructor - destroy a librdf_storage object. storage : librdf_storage object librdf_storage_openint librdf_storage_open (librdf_storage *storage, librdf_model *model); Start a model / storage association. This is ended with librdf_storage_close() storage : librdf_storage object model : model stored Returns : non 0 on failure librdf_storage_closeint librdf_storage_close (librdf_storage *storage); End a model / storage association. storage : librdf_storage object Returns : non 0 on failure librdf_storage_sizeint librdf_storage_size (librdf_storage *storage); Get the number of statements stored. storage : librdf_storage object Returns : The number of statements or < 0 if cannot be determined librdf_storage_add_statementint librdf_storage_add_statement (librdf_storage *storage, librdf_statement *statement); Add a statement to a storage. The passed-in statement is copied when added to the store, not shared with the store. If the statement already exists in the store, it is not added unless Redland contexts are being used. Enforces that the statement is legal for RDF - URI or blank subject, URI predicate and URI or blank or literal object (i.e. anything). storage : librdf_storage object statement : librdf_statement statement to add Returns : non 0 on failure, <0 on error, >0 if statement was illegal librdf_storage_add_statementsint librdf_storage_add_statements (librdf_storage *storage, librdf_stream *statement_stream); Add a stream of statements to the storage. If any of the statements already exists in the store, they are not added unless Redland contexts are being used. storage : librdf_storage object statement_stream : librdf_stream of statements Returns : non 0 on failure librdf_storage_remove_statementint librdf_storage_remove_statement (librdf_storage *storage, librdf_statement *statement); Remove a statement from the storage. storage : librdf_storage object statement : librdf_statement statement to remove Returns : non 0 on failure librdf_storage_contains_statementint librdf_storage_contains_statement (librdf_storage *storage, librdf_statement *statement); Test if a given statement is present in the storage. storage : librdf_storage object statement : librdf_statement statement to check Returns : non 0 if the storage contains the statement (>0 if illegal statement) librdf_storage_serialiselibrdf_stream* librdf_storage_serialise (librdf_storage *storage); Serialise the storage as a librdf_stream of statemetns. storage : librdf_storage object Returns : librdf_stream of statements or NULL on failure librdf_storage_find_statementslibrdf_stream* librdf_storage_find_statements (librdf_storage *storage, librdf_statement *statement); Search the storage for matching statements. Searches the storage for a (partial) statement as described in librdf_statement_match() and returns a librdf_stream of matching librdf_statement objects. storage : librdf_storage object statement : librdf_statement partial statement to find Returns : librdf_stream of matching statements (may be empty) or NULL on failure librdf_storage_find_statements_with_optionslibrdf_stream* librdf_storage_find_statements_with_options (librdf_storage *storage, librdf_statement *statement, librdf_node *context_node, librdf_hash *options); Search the storage for matching statements with match options. Searches the storage for a (partial) statement as described in librdf_statement_match() and returns a librdf_stream of matching librdf_statement objects. If options is given then the match is made according to the given options. If options is NULL, this is equivalent to librdf_storage_find_statements_in_context. storage : librdf_storage object statement : librdf_statement partial statement to find context_node : librdf_node context node or NULL. options : librdf_hash of matching options or NULL Returns : librdf_stream of matching statements (may be empty) or NULL on failure librdf_storage_get_sourceslibrdf_iterator* librdf_storage_get_sources (librdf_storage *storage, librdf_node *arc, librdf_node *target); Return the sources (subjects) of arc in an RDF graph given arc (predicate) and target (object). Searches the storage for arcs matching the given arc and target and returns a list of the source librdf_node objects as an iterator storage : librdf_storage object arc : librdf_node arc target : librdf_node target Returns : librdf_iterator of librdf_node objects (may be empty) or NULL on failure librdf_storage_get_arcslibrdf_iterator* librdf_storage_get_arcs (librdf_storage *storage, librdf_node *source, librdf_node *target); Return the arcs (predicates) of an arc in an RDF graph given source (subject) and target (object). Searches the storage for arcs matching the given source and target and returns a list of the arc librdf_node objects as an iterator storage : librdf_storage object source : librdf_node source target : librdf_node target Returns : librdf_iterator of librdf_node objects (may be empty) or NULL on failure librdf_storage_get_targetslibrdf_iterator* librdf_storage_get_targets (librdf_storage *storage, librdf_node *source, librdf_node *arc); Return the targets (objects) of an arc in an RDF graph given source (subject) and arc (predicate). Searches the storage for targets matching the given source and arc and returns a list of the source librdf_node objects as an iterator storage : librdf_storage object source : librdf_node source arc : librdf_node arc Returns : librdf_iterator of librdf_node objects (may be empty) or NULL on failure librdf_storage_get_arcs_inlibrdf_iterator* librdf_storage_get_arcs_in (librdf_storage *storage, librdf_node *node); Return the properties pointing to the given resource. storage : librdf_storage object node : librdf_node resource node Returns : librdf_iterator of librdf_node objects (may be empty) or NULL on failure librdf_storage_get_arcs_outlibrdf_iterator* librdf_storage_get_arcs_out (librdf_storage *storage, librdf_node *node); Return the properties pointing from the given resource. storage : librdf_storage object node : librdf_node resource node Returns : librdf_iterator of librdf_node objects (may be empty) or NULL on failure librdf_storage_has_arc_inint librdf_storage_has_arc_in (librdf_storage *storage, librdf_node *node, librdf_node *property); Check if a node has a given property pointing to it. storage : librdf_storage object node : librdf_node resource node property : librdf_node property node Returns : non 0 if arc property does point to the resource node librdf_storage_has_arc_outint librdf_storage_has_arc_out (librdf_storage *storage, librdf_node *node, librdf_node *property); Check if a node has a given property pointing from it. storage : librdf_storage object node : librdf_node resource node property : librdf_node property node Returns : non 0 if arc property does point from the resource node librdf_storage_context_add_statementint librdf_storage_context_add_statement (librdf_storage *storage, librdf_node *context, librdf_statement *statement); Add a statement to a storage in a context. If context is NULL, this is equivalent to librdf_storage_add_statement storage : librdf_storage object context : librdf_node context node statement : librdf_statement statement to add Returns : non 0 on failure librdf_storage_context_add_statementsint librdf_storage_context_add_statements (librdf_storage *storage, librdf_node *context, librdf_stream *stream); Add statements to a storage with a context. If context is NULL, this is equivalent to librdf_storage_add_statements storage : librdf_storage object context : librdf_node context stream : librdf_stream stream object Returns : Non 0 on failure librdf_storage_context_remove_statementint librdf_storage_context_remove_statement (librdf_storage *storage, librdf_node *context, librdf_statement *statement); Remove a statement from a storage in a context. If context is NULL, this is equivalent to librdf_storage_remove_statement storage : librdf_storage object context : librdf_node context node statement : librdf_statement statement to remove Returns : non 0 on failure librdf_storage_context_remove_statementsint librdf_storage_context_remove_statements (librdf_storage *storage, librdf_node *context); Remove statements from a storage with the given context. storage : librdf_storage object context : librdf_uri context Returns : Non 0 on failure librdf_storage_context_as_streamlibrdf_stream* librdf_storage_context_as_stream (librdf_storage *storage, librdf_node *context); List all statements in a storage context. storage : librdf_storage object context : librdf_node context node Returns : librdf_stream of statements or NULL on failure or context is empty librdf_storage_context_serialiselibrdf_stream* librdf_storage_context_serialise (librdf_storage *storage, librdf_node *context); List all statements in a storage context (DEPRECATED). DEPRECATED to reduce confusion with the librdf_serializer class. Please use librdf_storage_context_as_stream. storage : librdf_storage object context : librdf_node context node Returns : librdf_stream of statements or NULL on failure or context is empty librdf_storage_supports_queryint librdf_storage_supports_query (librdf_storage *storage, librdf_query *query); Check if a storage system supports a query language. Not implemented. storage : librdf_storage object query : librdf_query query object Returns : non-0 if the query is supported. librdf_storage_query_executelibrdf_query_results* librdf_storage_query_execute (librdf_storage *storage, librdf_query *query); Run the given query against the storage. Not implemented. storage : librdf_storage object query : librdf_query query object Returns : librdf_query_results or NULL on failure librdf_storage_syncint librdf_storage_sync (librdf_storage *storage); Synchronise the storage to the storage implementation. storage : librdf_storage object Returns : non-0 on failure librdf_storage_find_statements_in_contextlibrdf_stream* librdf_storage_find_statements_in_context (librdf_storage *storage, librdf_statement *statement, librdf_node *context_node); Search the storage for matching statements in a given context. Searches the storage for a (partial) statement as described in librdf_statement_match() in the given context and returns a librdf_stream of matching librdf_statement objects. If context is NULL, this is equivalent to librdf_storage_find_statements. storage : librdf_storage object statement : librdf_statement partial statement to find context_node : context librdf_node (or NULL) Returns : librdf_stream of matching statements (may be empty) or NULL on failure librdf_storage_get_contextslibrdf_iterator* librdf_storage_get_contexts (librdf_storage *storage); Return the list of contexts in the store. Returns an iterator of librdf_node context nodes for each context in the store. storage : librdf_storage object Returns : librdf_iterator of context nodes or NULL on failure or if contexts are not supported librdf_storage_get_featurelibrdf_node* librdf_storage_get_feature (librdf_storage *storage, librdf_uri *feature); Get the value of a storage feature. storage : librdf_storage object feature : librdf_uri feature property Returns : new librdf_node feature value or NULL if no such feature exists or the value is empty. librdf_storage_set_featureint librdf_storage_set_feature (librdf_storage *storage, librdf_uri *feature, librdf_node *value); Set the value of a storage feature. storage : librdf_storage object feature : librdf_uri feature property value : librdf_node feature property value Returns : non 0 on failure (negative if no such feature) librdf_storage_transaction_commitint librdf_storage_transaction_commit (librdf_storage *storage); Commit a transaction. storage : the storage object Returns : non-0 on failure librdf_storage_transaction_get_handlevoid* librdf_storage_transaction_get_handle (librdf_storage *storage); Get the current transaction handle. storage : the storage object Returns : non-0 on failure librdf_storage_transaction_rollbackint librdf_storage_transaction_rollback (librdf_storage *storage); Rollback a transaction. storage : the storage object Returns : non-0 on failure librdf_storage_transaction_startint librdf_storage_transaction_start (librdf_storage *storage); Start a transaction storage : the storage object Returns : non-0 on failure librdf_storage_transaction_start_with_handleint librdf_storage_transaction_start_with_handle (librdf_storage *storage, void *handle); Start a transaction using an existing external transaction object. storage : the storage object handle : the transaction object Returns : non-0 on failure librdf_storage_add_referencevoid librdf_storage_add_reference (librdf_storage *storage); Increment storage reference count by one. This function is intended to be internal to librdf storage modules. storage : librdf_storage object librdf_storage_remove_referencevoid librdf_storage_remove_reference (librdf_storage *storage); Decrement storage reference count by one. Free the storage if reference count becomes zero. This function is intended to be internal to librdf storage modules. storage : librdf_storage object