US 2013/0159278 A1 · TECHNIQUES FOR EFFICIENTLY SUPPORTING XQUERY UPDATE FACILITY IN SQL/XML

Abstract

The approaches described herein provide an efficient way to process certain kinds of queries that update XML data stored in an object-relational database. A query may include an XML query expression that conforms to a language for querying XML documents. A technique first determines whether the query contains an XML updating expression, and in response rewrites the query to comprise one or more path-based query operators that specify operations for updating XML data. The query may then be further rewritten to comprise one or more storage format specific query operators based on the particular database storage format associated with the XML data specified in the query. The rewritten query operators are used to generate a query execution plan that provides for several query execution optimizations.

Claims16

Dependent claims

A method comprising:

receiving a query expression against a collection of XML documents stored in one or more tables of a database, wherein the collection of XML documents are stored based on a particular data storage format;
determining that the query expression contains an updating expression that conforms to a language for querying XML documents;
in response to determining that the query expression contains an updating expression, rewriting the query expression to form a first rewritten query expression comprising one or more path-based query operators that specify operations for updating XML data;
based on the particular database storage format storing the collection of XML documents, rewriting the first rewritten query expression to form a second rewritten query expression comprising one or more storage format specific query operators configured to update particular XML data of the collection of XML documents;
and
wherein the method is performed by one or more computing devices.

3 more elements

A non-transitory computer-readable medium storing instructions which, when executed by one or more processors, cause the one or more processors to perform a method, comprising:

receiving a query expression against a collection of XML documents stored in one or more tables of a database, wherein the collection of XML documents are stored based on a particular data storage format;
determining that the query expression contains an updating expression that conforms to a language for querying XML documents;
in response to determining that the query expression contains an updating expression, rewriting the query expression to form a first rewritten query expression comprising one or more path-based query operators that specify operations for updating XML data;
based on the particular database storage format storing the collection of XML documents, rewriting the first rewritten query expression to form a second rewritten query expression comprising one or more storage format specific query operators configured to update particular XML data of the collection of XML documents.

1 more element

Dependencies are inferred from the claim text.

Techniques for efficiently supporting xquery update facility in sql/xml

Life of this patent

Techniques for efficiently supporting xquery update facility in sql/xml

Life of this patent

Abstract

Claims16