BBTC: A New Update-Supporting Coding Scheme for XML Documents

The identification of parent-child or ancestor-descendant relationship between XML elements plays a crucial role in efficient XML query processing. One popular method is to code each node in the XML document tree. However, its main problem is that either lacks the ability to support XML documents update or need huge storage space. This paper proposes a new update-supporting coding scheme based on binary-tree to identify the ancestor-descendant relationship or the parent-child relationship in constant time bound, which also effectively supports XML documents update. To reduce the coding space, we then propose a new storage approach, Blocked Binary-Tree Coding scheme (BBTC), whose average code length reduces to O(log(n)). Our extensive experiments show that BBTC significantly outperforms previous ones.