cadmium-org / cadmium-cms

		 * @return bool : true on success or false on failure

		 */

		private function disconnectSubtree() : bool {

			$query = ("DELETE rla FROM " . static::$table_relations . " rla ") .

			         ("JOIN "  . static::$table_relations . " rlb ON rlb.descendant = rla.descendant ") .

			         ("LEFT JOIN " . static::$table_relations . " rlx ") .

			         ("ON rlx.ancestor = rlb.ancestor AND rlx.descendant = rla.ancestor ") .

			         ("WHERE rlb.ancestor = " . $this->id . " AND rlx.ancestor IS NULL");

			if (!(DB::send($query) && DB::getLast()->status)) return false;

			# Set path

			$this->dataset->update(['parent_id' => 0]);

			# ------------------------

			return true;

		}

		/**

		 * Connect the subtree under the new position

		 * @return bool : true on success or false on failure

		 */

		private function connectSubtree(int $parent_id) : bool {

			$query = ("INSERT INTO " . static::$table_relations . " (ancestor, descendant, depth) ") .

			         ("SELECT sup.ancestor, sub.descendant, sup.depth + sub.depth + 1 ") .

			         ("FROM " . static::$table_relations . " sup ") .

			         ("JOIN " . static::$table_relations . " sub ") .

			         ("WHERE sub.ancestor = " . $this->id . " AND sup.descendant = " . $parent_id);

			if (!(DB::send($query) && (DB::getLast()->rows > 0))) return false;

			# Set path

			$this->dataset->update(['parent_id' => $parent_id]);

			# ------------------------

			return true;

		}

		/**

		 * Create the entity entry in DB