Context-Preserving XQuery Fusion

نویسندگان

  • Hiroyuki Kato
  • Soichiro Hidaka
  • Zhenjiang Hu
  • Keisuke Nakano
  • Yasunori Ishihara
چکیده

XQuery is a DBPL for querying XML databases. The semantics of XQuery is context sensitive and requires preservation of document order. In this paper, we propose, as far as we are aware, the first XQuery fusion that can deal with both the document order and the context of XQuery expressions. More specifically, we carefully design a context representation of XQuery expressions based on the Dewey order encoding, develop a context-preserving XQuery fusion for ordered trees by static emulation of the XML store, and prove that our fusion is correct. Our XQuery fusion has been implemented, and all the examples in this paper have passed the system.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

GRACE TECHNICAL REPORTS Context-Preserving XQuery Fusion

XQuery is a DBPL for querying XML databases. The semantics of XQuery is context sensitive and requires preservation of document order. In this paper, we propose, as far as we are aware, the first XQuery fusion that can deal with both the document order and the context of XQuery expressions. More specifically, we carefully design a context representation of XQuery expressions based on the Dewey ...

متن کامل

Rewriting XQuery to Avoid Redundant Expressions based on Static Emulation of XML Store

Rewriting composite expressions based on eliminating intermediate results generated by redundant expressions is a traditional optimization technique (known as fusion) in both programming languages community and database community. In XQuery, composite expressions for node creation are typical in practice, for example, in data integration systems for XML with XQuery as schema mapping. We propose...

متن کامل

Constructing Optimal Bushy Trees Possibly Containing Cross Products for Order Preserving Joins is in P

One of the main features of XQuery compared to traditional query languages like SQL, is that it preserves the input order—unless specified otherwise. As a consequence, order-preserving algebraic operators are needed to capture the semantics of XQuery correctly. One important algebraic operator is the orderpreserving join. The order-preserving join is associative but, in contrast to the traditio...

متن کامل

Quantifiers in XQuery

We present algebraic equivalences that allow to unnest nested algebraic expressions containing quantifiers for order-preserving algebraic operators. We illustrate how these equivalences can be applied successfully to unnest nested queries formulated in XQuery. Measurements illustrate the performance gains possible by unnesting.

متن کامل

Three Cases for Query Decorrelation in XQuery

We present algebraic equivalences that allow to unnest nested algebraic expressions for order-preserving algebraic operators. We illustrate how these equivalences can be applied successfully to unnest nested queries given in the XQuery language. Measurements illustrate the performance gains possible our approach.

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Mathematical Structures in Computer Science

دوره 25  شماره 

صفحات  -

تاریخ انتشار 2010