| 摘要 |
<p>A coupled node tree has a root node (101, 210a) and a node pair (111,201b, 201c) the node pair being a branch node (112, 211c), which includes position information (116, 221c) of a link target node pair, and a leaf node (113, 210c), which includes a search target index key (118, 250c) or a pair of branch nodes, or a pair of leaf nodes located in adjacent storage areas. The nodes of the coupled node tree are backed up in a depth precedence search sequence. The coupled node tree is restored by repeating the following process: reading out the nodes in the sequence they are backed up, storing in a stack the position information of the node to be restored, successively restoring child nodes as long as branch nodes are encountered, restoring a leaf node which is read out and then, tracing back up the stack, a decision being made as to which node is next to be restored.</p> |
