def delete_index_node(self, index_node): block, index_node = self.find_index_block(index_node) if block is None: print("Fail") return successor_block, successor_node = self.find_successor(block, index_node) if block == successor_block: successor_node.set_index_block_pointer(index_node.get_index_block_pointer()) block.delete_index_node(index_node) if len(block.get_index_nodes()) == 1: if block.get_location() != self.get_root_block(): parent_location = block.get_parent_block() if parent_location != -1: parent = IndexBlock(parent_location, self._index_name, self._index_directory) parent.read_block(self._fd) for node in parent.get_index_nodes(): if node.get_index_block_pointer() == block.get_location(): node.set_index_block_pointer(block.get_index_nodes()[0].get_index_block_pointer()) parent.update_child_blocks(self._fd) parent.write_block(self._fd) block.delete_block(self._fd, self.get_free_block_pointer()) else: block.write_block(self._fd) else: block.write_block(self._fd) else : successor_block.delete_index_node(successor_node) block.delete_index_node(index_node) successor_node.set_index_block_pointer(index_node.get_index_block_pointer()) block.add_index_node(successor_node) block.write_block(self._fd) if len(successor_block.get_index_nodes()) == 1: if successor_block.get_location() != self.get_root_block(): parent_location = successor_block.get_parent_block() if parent_location != -1: parent = IndexBlock(parent_location, self._index_name, self._index_directory) parent.read_block(self._fd) for node in parent.get_index_nodes(): if node.get_index_block_pointer() == successor_block.get_location(): node.set_index_block_pointer(successor_block.get_index_nodes()[0].get_index_block_pointer()) parent.update_child_blocks(self._fd) parent.write_block(self._fd) successor_block.delete_block(self._fd, self.get_free_block_pointer()) else: successor_block.write_block(self._fd) else: successor_block.write_block(self._fd)
def split_block(self, block): index_nodes = block.get_index_nodes() median = int(len(index_nodes)/2 - 1) median_node = index_nodes[median] new_block = IndexBlock(self.get_free_block_pointer(), self._index_name, self._index_directory) new_block.create_dummy_node() i = 0 while i < median: new_block.add_index_node(index_nodes[i]) i += 1 new_block.get_index_nodes()[-1].set_index_block_pointer(median_node.get_index_block_pointer()) i = 0 while i <= median: block.delete_index_node(index_nodes[0]) i += 1 new_block.update_child_blocks(self._fd) median_node.set_index_block_pointer(new_block.get_location()) new_block.set_parent_block(block.get_parent_block()) return new_block, median_node