Oracle International Corporation

Rohan Angrish

Zhen Hua Liu

Muralidhar Krishnaprasad

James W Warner

Vikas Arora

Anand Manikutty

Susan M Kotsovolos

Ravi Murthy

Ying Lu

Hui Zhang

Karuna Muthiah

Nipun Agarwal

Wesley Lin

Abhyudaya Agrawal

A database server that manages a database retrieves metadata that is stored, within the database, in association with a procedure that is stored in the database. Based on the metadata, a Web service definition is automatically constructed to describe the procedure as a Web service. The WSDL definition can be referenced to construct SOAP messages with the appropriate arguments and in the appropriate format which, when received, are converted to a suitable format for invoking execution of the procedure by the database server.

Techniques for automatically exposing, as web services, procedures and functions stored in a database

In one embodiment, a database server receives a request from a spreadsheet application to open a file with spreadsheet data. The spreadsheet data is stored in one or more relational tables in one or more relational databases that are managed by the database server. In response to the request, the database server generates the file, where generating the file comprises retrieving the spreadsheet data from an XML view that is defined by an XQuery query. When executed, the XQuery query returns the spreadsheet data in an XML spreadsheet format that is understood by the spreadsheet application. The database server provides the generated file with the spreadsheet data directly to the spreadsheet application, where the spreadsheet data as retrieved from the XML view is formatted according to the XML spreadsheet format.

Techniques for query and DML over relational tables using spreadsheet applications

An XQuery access API is described, for providing access to XML data from a data source, using the XQuery language. A requestor can request, from a server, performance of an operation on XML data, wherein request messages and response messages conform to the Simple Object Access Protocol (SOAP). Request and response messages can be transmitted using Hypertext Transfer Protocol (HTTP) or Hypertext Transfer Protocol over Secure Socket Layer (HTTPS). The format of the request and response messages is specified in a definition of a Web service, where the definition conforms to the Web Service Description Language (WSDL).

Techniques for providing XQuery access using web services

Using a WSDL document to exchange an interface definition for back-end business logic includes automatically mapping various elements of the WSDL document to corresponding XQuery elements to generate an XQuery interface definition 'skeleton'. From such an XQuery interface skeleton, an XQuery statement can be generated by filling in the body of the function that implements the logic. The XQuery statement serves as an interface definition for an interface to the function. Furthermore, at runtime a Web Service request that is based on the WSDL document can be translated into an XQuery call into an XQuery function that implements the logic defined in the WSDL document. From there, results are obtained from the XQuery function, translated into the appropriate return format defined in the WSDL, and returned.

Mapping web services description language documents to XQuery functions

Optimization is provided for database statements involving XML data, e.g., XPath and XQuery, which operate over views that use aggregate set operators, e.g., UNION ALL. As part of a 'view merge' stage of query transformation, the query that operates over the view is merged with a query that defines the view. One or more expressions (e.g., operators, predicates, virtual table constructs) from the query that operates over the view are then 'pushed down' to operate on the individual underlying XML data constructs. &#x201c;Branch elimination&#x201d; is performed based on the structure of the view and the query acting over the view, based on which it is possible to determine whether any of the sub-queries, if executed, would result in the return of zero rows. If so, then such branches are eliminated from the transformed query, leaving a reduced set of data containers on which to execute the query.

Optimization of queries over XML views that are based on union all operators

To associate XML data objects ('child objects'), stored in rows of relational or object-relational tables, with the appropriate XML data objects ('parent objects') from which the child objects descend, tables that contain child objects (&#x201c;out-of-line&#x201d; tables) are constructed with an additional column. In one embodiment, this column stores values that identify the root objects, in the appropriate table, from which the respective child objects descend. Hence, the root object from which any given object descends is traceable by following the respective value back to the corresponding root object. In one embodiment, this column stores values that identify the complete XML hierarchical path, through multiple tables, back to the root object from which the respective child objects descend. Consequently, XML query language queries against XML documents stored in such tables can be rewritten as SQL queries against the data in the tables, even in the presence of cyclic constructs.

Techniques for efficiently storing and querying in a relational database, XML documents conforming to schemas that contain cyclic constructs

Techniques are described for executing queries that have XPath sections that specify unmappable paths. The techniques involve splitting the unmappable paths into (1) a mappable path fragment, and (2) an unmappable path fragment. After an unmappable path has been split into a mappable path fragment and an unmappable path fragment, the XPath section is replaced with a replacement XPath section. The replacement XPath section specifies two operations: a 'mappable operation' that is based on the mappable path fragment, and an 'unmappable operation' that is based on the unmappable path fragment. The portion of the replacement XPath section that specifies the mappable operation is rewritten to access underlying relational structures. Consequently, when the rewritten query is executed, a smaller amount of XML data needs to be materialized to evaluate the unmappable path fragment than would otherwise have been required to evaluate the original unmappable path.

Techniques for partial rewrite of XPath queries in a relational database

A method and apparatus for rewriting a database command containing an embedded XML expression such that the rewritten database command recites a text function, in lieu of the embedded XML expression, is provided. Advantageously, a DBMS may take advantage of the efficiencies in storing XML data within the database, while avoiding the generation of unnecessary XML elements in processing the query when the XML elements contribute nothing to the outcome of the query. Cost-base or rule-based analysis may be performed to determine how to rewrite a received database command. The database server may functionally evaluate the text function or may use an index defined on a column of the database. The text function may function as a primary filter or may reference a column upon which an index is defined, wherein the index operates at the same or higher level than a column being referenced in the embedded XML expression.

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Redwood City, CA, United States of America

Rohan Angrish