Class
TrackerSparqlStatement
Description [src]
abstract class Tracker.SparqlStatement : GObject.Object
{
/* No available fields */
}TrackerSparqlStatement represents a prepared statement for a SPARQL query.
The SPARQL query will be internally compiled into the format that is most
optimal to execute the query many times. For connections created
through tracker_sparql_connection_new() that will be a
SQLite compiled statement.
The SPARQL query may contain parameterized variables expressed via the
~ prefix in the SPARQL syntax (e.g. ~var), these may happen anywhere
in the SPARQL where a literal or variable would typically happen. These
parameterized variables may be mapped to arbitrary values prior to
execution. The TrackerSparqlStatement may be reused for future
queries with different values.
The argument bindings may be changed through the tracker_sparql_statement_bind_int(),
tracker_sparql_statement_bind_int(), etc… family of functions. Those functions
receive a name argument corresponding for the variable name in the SPARQL query
(eg. "var" for ~var) and a value to map the variable to.
Once all arguments have a value, the query may be executed through
tracker_sparql_statement_execute_async() or tracker_sparql_statement_execute().
It is possible to use any TrackerSparqlStatement from other threads than
the one it was created from. However, binding values and executing the
statement must only happen from one thread at a time. It is possible to reuse
the TrackerSparqlStatement right after tracker_sparql_statement_execute_async()
was called, there is no need to wait for tracker_sparql_statement_execute_finish().
In some circumstances, it is possible that the query needs to be recompiled from the SPARQL source. This will happen transparently.
Instance methods
tracker_sparql_statement_bind_boolean
Binds the boolean value to the parameterized variable given by name.
tracker_sparql_statement_bind_datetime
Binds the GDateTime value to the parameterized variable given by name.
since: 3.2
tracker_sparql_statement_bind_double
Binds the double value to the parameterized variable given by name.
tracker_sparql_statement_bind_int
Binds the integer value to the parameterized variable given by name.
tracker_sparql_statement_bind_langstring
Binds the value to the parameterized variable given by name, tagged
with the language defined by langtag. The language tag should follow
RFC 5646. The parameter
will be represented as a rdf:langString.
since: 3.7
tracker_sparql_statement_bind_string
Binds the string value to the parameterized variable given by name.
tracker_sparql_statement_execute
Executes the SELECT or ASK SPARQL query with the currently bound values.
tracker_sparql_statement_execute_async
Executes asynchronously the SELECT or ASK SPARQL query with the currently bound values.
tracker_sparql_statement_execute_finish
Finishes the asynchronous operation started through
tracker_sparql_statement_execute_async().
tracker_sparql_statement_get_connection
Returns the TrackerSparqlConnection that this statement was created for.
tracker_sparql_statement_serialize_async
Serializes a DESCRIBE or CONSTRUCT query into the given RDF format.
since: 3.3
tracker_sparql_statement_serialize_finish
Finishes the asynchronous operation started through
tracker_sparql_statement_serialize_async().
since: 3.3
tracker_sparql_statement_update
Executes the INSERT/DELETE SPARQL query series with the currently bound values.
since: 3.5
tracker_sparql_statement_update_async
Executes asynchronously the INSERT/DELETE SPARQL query series with the currently bound values.
since: 3.5
tracker_sparql_statement_update_finish
Finishes the asynchronous update started through
tracker_sparql_statement_update_async().
since: 3.5
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.