def execute(self, statement, params=None, noresult=False):
"""Execute a statement with the given parameters.
@type statement: L{Expr} or C{str}
@param statement: The statement to execute. It will be
compiled if necessary.
@param noresult: If True, no result will be returned.
@raise ConnectionBlockedError: Raised if access to the connection
has been blocked with L{block_access}.
@raise DisconnectionError: Raised when the connection is lost.
Reconnection happens automatically on rollback.
@return: The result of C{self.result_factory}, or None if
C{noresult} is True.
"""
if self._closed:
raise ClosedError("Connection is closed")
if self._blocked:
raise ConnectionBlockedError("Access to connection is blocked")
if self._event:
self._event.emit("register-transaction")
self._ensure_connected()
if isinstance(statement, Expr):
if params is not None:
raise ValueError("Can't pass parameters with expressions")
state = State()
statement = self.compile(statement, state)
params = state.parameters
statement = convert_param_marks(statement, "?", self.param_mark)
raw_cursor = self.raw_execute(statement, params)
if noresult:
self._check_disconnect(raw_cursor.close)
return None
return self.result_factory(self, raw_cursor)
def _ensure_connected(self):
"""Ensure that we are connected to the database.
If the connection is marked as dead, or if we can't reconnect,
then raise DisconnectionError.
"""
if self._blocked:
raise ConnectionBlockedError("Access to connection is blocked")
if self._state == STATE_CONNECTED:
return
elif self._state == STATE_DISCONNECTED:
raise DisconnectionError("Already disconnected")
elif self._state == STATE_RECONNECT:
try:
self._raw_connection = self._database.raw_connect()
except DatabaseError as exc:
self._state = STATE_DISCONNECTED
self._raw_connection = None
raise DisconnectionError(str(exc))
else:
self._state = STATE_CONNECTED