Holistic twig joins: optimal XML pattern matching
Proceedings of the 2002 ACM SIGMOD international conference on Management of data
Efficient processing of XML twig queries with OR-predicates
SIGMOD '04 Proceedings of the 2004 ACM SIGMOD international conference on Management of data
FleXPath: flexible structure and full-text querying for XML
SIGMOD '04 Proceedings of the 2004 ACM SIGMOD international conference on Management of data
Efficient processing of XML twig patterns with parent child edges: a look-ahead approach
Proceedings of the thirteenth ACM international conference on Information and knowledge management
On the memory requirements of XPath evaluation over XML streams
PODS '04 Proceedings of the twenty-third ACM SIGMOD-SIGACT-SIGART symposium on Principles of database systems
On boosting holism in XML twig pattern matching using structural indexing techniques
Proceedings of the 2005 ACM SIGMOD international conference on Management of data
Efficient algorithms for processing XPath queries
ACM Transactions on Database Systems (TODS)
Stack-based algorithms for pattern matching on DAGs
VLDB '05 Proceedings of the 31st international conference on Very large data bases
Semantic querying of tree-structured data sources using partially specified tree patterns
Proceedings of the 14th ACM international conference on Information and knowledge management
Holistic twig joins on indexed XML documents
VLDB '03 Proceedings of the 29th international conference on Very large data bases - Volume 29
VLDB '04 Proceedings of the Thirtieth international conference on Very large data bases - Volume 30
Evaluation of partial path queries on xml data
Proceedings of the sixteenth ACM conference on Conference on information and knowledge management
Assigning semantics to partial tree-pattern queries
Data & Knowledge Engineering
Querying complex structured databases
VLDB '07 Proceedings of the 33rd international conference on Very large data bases
Multi-dimensional search for personal information management systems
EDBT '08 Proceedings of the 11th international conference on Extending database technology: Advances in database technology
Efficient evaluation of generalized path pattern queries on XML data
Proceedings of the 17th international conference on World Wide Web
Containment of partially specified tree-pattern queries in the presence of dimension graphs
The VLDB Journal — The International Journal on Very Large Data Bases
Efficient evaluation of partial path queries over a XML compact storage structure
Proceedings of the International Conference on Advances in Computing, Communications and Informatics
A survey on XML streaming evaluation techniques
The VLDB Journal — The International Journal on Very Large Data Bases
Optimizing XML queries: Bitmapped materialized views vs. indexes
Information Systems
Hi-index | 0.00 |
Querying XML data is based on the specification of structural patterns which in practice are formulated using XPath. Usually, these structural patterns are in the form of trees (Tree-Pattern Queries --- TPQs). Requirements for flexible querying of XML data including XML data from scientific applications have motivated recently the introduction of query languages that are more general and flexible than TPQs. These query languages correspond to a fragment of XPath larger than TPQs for which efficient non-main-memory evaluation algorithms are not known. In this paper, we consider a query language, called Partial Tree-Pattern Query (PTPQ) language, which generalizes and strictly contains TPQs. PTPQs represent a broad fragment of XPath which is very useful in practice. We show how PTPQs can be represented as directed acyclic graphs augmented with "same-path" constraints. We develop an original polynomial time holistic algorithm for PTPQs under the inverted list evaluation model. To the best of our knowledge, this is the first algorithm to support the evaluation of such a broad structural fragment of XPath. We provide a theoretical analysis of our algorithm and identify cases where it is asymptotically optimal. In order to assess its performance, we design two other techniques that evaluate PTPQs by exploiting the state-of-the-art existing algorithms for smaller classes of queries. An extensive experimental evaluation shows that our holistic algorithm outperforms the other ones.