|  |  |  | Rasqal RDF Query Library Manual |  | 
|---|---|---|---|---|
| Top | Description | ||||
rasqal_data_graph; rasqal_data_graph * rasqal_new_data_graph_from_data_graph (rasqal_data_graph *dg); rasqal_data_graph * rasqal_new_data_graph_from_iostream (rasqal_world *world,raptor_iostream *iostr,raptor_uri *base_uri,raptor_uri *name_uri,unsigned int flags,const char *format_type,const char *format_name,raptor_uri *format_uri); rasqal_data_graph * rasqal_new_data_graph_from_uri (rasqal_world *world,raptor_uri *uri,raptor_uri *name_uri,int flags,const char *format_type,const char *format_name,raptor_uri *format_uri); void rasqal_free_data_graph (rasqal_data_graph *dg); enum rasqal_data_graph_flags; int rasqal_data_graph_print (rasqal_data_graph *dg,FILE *fh);
Data graphs are used in the query to describe RDF graphs that can be used to query against. The graphs can be used either with raptor_uri to name the graph, or without a name. The query language determines which graphs are used in the query.
typedef struct {
  rasqal_world* world;
  raptor_uri* uri;
  raptor_uri* name_uri;
  int flags;
  char* format_type;
  char* format_name;
  raptor_uri* format_uri;
  raptor_iostream* iostr;
  raptor_uri* base_uri;
  int usage;
} rasqal_data_graph;
A source of RDF data for querying.
If iostr is present, the graph can be constructed by parsing the
iostream and using base_uri as a base uri. Otherwise the graph
can be constructed from the graph at URI uri.
In either case the name_uri is the graph name as long as flags
is RASQAL_DATA_GRAPH_NAMED
| rasqal_world * | rasqal_world object | 
| raptor_uri * | source URI | 
| raptor_uri * | name of graph for RASQAL_DATA_GRAPH_NAMED | 
| RASQAL_DATA_GRAPH_NAMEDorRASQAL_DATA_GRAPH_BACKGROUND | |
| MIME Type of data format at uri(or NULL) | |
| Raptor parser Name of data format at uri(or NULL) | |
| raptor_uri * | URI of data format at uri(or NULL) | 
| raptor_iostream * | Raptor iostream for content, overriding uriif present (or NULL) | 
| raptor_uri * | base URI for reading from iostream | 
| usage count of this object | 
rasqal_data_graph * rasqal_new_data_graph_from_data_graph
                                                        (rasqal_data_graph *dg);
Copy Constructor - create a new rasqal_data_graph object from an existing rasqal_data_graph object.
| 
 | rasqal_data_graph object to copy or NULL | 
| Returns : | a new rasqal_data_graph object or NULL if dgwas NULL. | 
rasqal_data_graph * rasqal_new_data_graph_from_iostream (rasqal_world *world,raptor_iostream *iostr,raptor_uri *base_uri,raptor_uri *name_uri,unsigned int flags,const char *format_type,const char *format_name,raptor_uri *format_uri);
Constructor - create a new rasqal_data_graph from iostream content
The name_uri is used when the flags are RASQAL_DATA_GRAPH_NAMED.
The base_uri is used to provide the Raptor parser a base URI.  If
a base URI is required but none is given, the parsing will fail
and the query that uses this data source will fail.
| 
 | rasqal_world object | 
| 
 | source graph format iostream | 
| 
 | base URI for iostream content | 
| 
 | name of graph (or NULL) | 
| 
 | RASQAL_DATA_GRAPH_NAMEDorRASQAL_DATA_GRAPH_BACKGROUND | 
| 
 | MIME Type of data format at uri(or NULL) | 
| 
 | Raptor parser Name of data format at uri(or NULL) | 
| 
 | URI of data format at uri(or NULL) | 
| Returns : | a new rasqal_data_graph or NULL on failure. | 
rasqal_data_graph * rasqal_new_data_graph_from_uri (rasqal_world *world,raptor_uri *uri,raptor_uri *name_uri,int flags,const char *format_type,const char *format_name,raptor_uri *format_uri);
Constructor - create a new rasqal_data_graph.
The name_uri is only used when the flags are RASQAL_DATA_GRAPH_NAMED.
| 
 | rasqal_world object | 
| 
 | source URI | 
| 
 | name of graph (or NULL) | 
| 
 | RASQAL_DATA_GRAPH_NAMEDorRASQAL_DATA_GRAPH_BACKGROUND | 
| 
 | MIME Type of data format at uri(or NULL) | 
| 
 | Raptor parser Name of data format at uri(or NULL) | 
| 
 | URI of data format at uri(or NULL) | 
| Returns : | a new rasqal_data_graph or NULL on failure. | 
void                rasqal_free_data_graph              (rasqal_data_graph *dg);
Destructor - destroy a rasqal_data_graph object.
| 
 | rasqal_data_graph object | 
typedef enum {
  RASQAL_DATA_GRAPH_NONE  = 0,
  RASQAL_DATA_GRAPH_NAMED = 1,
  RASQAL_DATA_GRAPH_BACKGROUND = 2,
} rasqal_data_graph_flags;
Flags for the type of rasqal_data_graph.
These are used by rasqal_new_data_graph_from_uri() and
rasqal_new_data_graph_from_iostream().  See rasqal_data_graph.
int rasqal_data_graph_print (rasqal_data_graph *dg,FILE *fh);
Print a Rasqal data graph in a debug format.
The print debug format may change in any release.
| 
 | rasqal_data_graph object | 
| 
 | the FILE* handle to print to | 
| Returns : | non-0 on failure |