Class
TrackerSparqlCursor
Description [src]
abstract class Tracker.SparqlCursor : GObject.Object
{
/* No available fields */
}TrackerSparqlCursor provides the methods to iterate the results of a SPARQL query.
Cursors are obtained through e.g. tracker_sparql_statement_execute()
or tracker_sparql_connection_query() after the SPARQL query has been executed.
When created, a cursor does not point to any element, tracker_sparql_cursor_next()
is necessary to iterate one by one to the first (and following) results.
When the cursor iterated across all rows in the result set, tracker_sparql_cursor_next()
will return FALSE with no error set.
On each row, it is possible to extract the result values through the
tracker_sparql_cursor_get_integer(), tracker_sparql_cursor_get_string(), etc… family
of methods. The column index of those functions starts at 0. The number of columns is
dependent on the SPARQL query issued, but may be checked at runtime through the
tracker_sparql_cursor_get_n_columns() method.
After a cursor is iterated, it is recommended to call tracker_sparql_cursor_close()
explicitly to free up resources for other users of the same TrackerSparqlConnection,
this is especially important in garbage collected languages. These resources
will be also implicitly freed on cursor object finalization.
It is possible to use a given TrackerSparqlCursor in other threads than
the one it was created from. It must be however used from just one thread
at any given time.
Instance methods
tracker_sparql_cursor_get_connection
Returns the TrackerSparqlConnection associated with this
TrackerSparqlCursor.
tracker_sparql_cursor_get_datetime
Retrieves a GDateTime pointer for the current row in column.
since: 3.2
tracker_sparql_cursor_get_langstring
Retrieves a string representation of the data in the current
row in column. If the string has language information (i.e. it is
a rdf:langString](rdf-ontology.html#rdf:langString)), the language
tag will be returned in the location provided through langtag. This
language tag will typically be in a format conforming
RFC 5646.
since: 3.7
tracker_sparql_cursor_get_string
Retrieves a string representation of the data in the current
row in column.
tracker_sparql_cursor_get_value_type
Returns the data type bound to the current row and the given column.
tracker_sparql_cursor_is_bound
Returns whether the given column has a bound value in the current row.
tracker_sparql_cursor_next_finish
Finishes the asynchronous iteration to the next result started with
tracker_sparql_cursor_next_async().
Signals
Signals inherited from GObject (1)
GObject::notify
The notify signal is emitted on an object when one of its properties has its value set through g_object_set_property(), g_object_set(), et al.