Patent Application: US-3761705-A

Abstract:
methods and systems for analyzing xml documents . the system scans an xml document , identifies different dimensions that span the xml document and detects scoping relationships amongst them . the system uses the dimensional information to create a logical hierarchical scoped dimension analysis model , maps the logical xml tree to this model , and then implements the analytical method over the logical model . the logical model allows both structural features and numeric / non - numeric data to be used for analysis . the analytical method allows users to query irregular structural properties of the xml documents using the xpath navigational api .

Description:
some background information of interest may be found in the copending and commonly assigned u . s . patent application entitled “ method and system for supporting structured aggregation operations on semi - structured data ”, which is filed concurrently with the instant application and which is hereby fully incorporated by reference as if set forth in its entirety herein . one embodiment of the present invention encompasses a logical hierarchical analysis model , called the scoped dimension analysis model , for analyzing semi - structured data such as xml documents . in another embodiment of the present invention , the scoped dimension analysis model is preferably integrated in a system with an xml parser and an xml query processor . for an xml document , the system first parses the document , identifies scoped dimensions that span the document and then populates the analysis model using nodes from the parsed xml document . in another embodiment of the present invention , the scoped dimension analysis model is used for implementing queries over semi - structured features of the xml document . the disclosure now turns to a discussion of the key features of the analysis system . for the purpose of discussion , the schematic illustrated in fig1 will be used . the system first parses an xml document ( 100 ) using a sax - or dom - based parser ( 102 ). as the document is being parsed , the parser invokes a scoped dimension analyzer ( 110 ) to identify dependent and independent dimensions and their scopes . the scoped dimension analyzer then preferably proceeds as follows : 1 . in an xml document , it operates only on xml element and attribute nodes . it neglects the remaining nodes . 2 . starting from the document root , every xml element or attribute node is marked as a dimension with the tag - name as its dimension name . 3 . other than the document root , every dimension is marked as a sub - dimension within the scope of its parent dimension ( i . e ., the dimension defined by the parent element of the current element or attribute node ). 4 . within the scope of a dimension , if a sub - dimension with a particular name exists , the sub - dimension is not added to a temporary data structure , called the scoped dimension descriptor ( 112 ). else , the sub - dimension is added as a child dimension within the scope of its parent dimension to create a scoped dimension hierarchy . all unique dimensions in a scoped dimension are considered independent within the scope of that dimension . further , all dimensions that have the same parent scope are considered independent over the scope of the entire xml document . for example , with brief reference to fig3 , which shows a scoped dimensional hierarchy , the dimension employee is independent over the entire document , whereas the dimension department is independent in the scope of its parent dimension only . further , all dimensions are dependent on their ancestor dimensions . once the document is parsed , the scoped dimension descriptor ( 112 ) and parsed document tree ( 104 ) ( generated by the parser , and a detailed illustrative exanple of which is shown in fig2 ) are passed to the analytical model builder ( 120 ). the builder generates the analytical model ( 122 ) by first recreating the dimension hierarchy and then assigning the xml element and attribute nodes to the appropriate nodes in the dimensional hierarchy . all text nodes are also assigned to their parent element or attribute nodes ( note that these parent nodes form the dependent dimensions of the document ). by way of brief reference , fig4 illustrates the populated analytical model : each node in the analytical model points to a list of nodes , sorted using the xml &# 39 ; s document order ( depth - first pre - order numbering ). the document tree 104 is also modified to insert references back to the analytical model . note that this approach does not require transformations of the source data as in the case of analyzing relational data . the disclosure now turns to a discussion of an execution of analysis methods over the analytical model . as fig1 illustrates , while executing an xml query ( 106 ) towards yielding results ( 108 ), the query processor ( 116 ) loads both the xml document tree and the corresponding analytical model . the xml query processor ( 116 ) preferably uses xpath api ( xpath is a language for addressing parts of an xml document , designed to be used by both xslt and xpointer ; a general discussion of xpath api may be found in the xpath standards document [ 6 ] to address and navigate through the xml tree . the analytical model ( 122 ) is mainly used for processing analysis queries . contemplated herein is the execution of three types of queries : ( 1 ) projection queries , ( 2 ) structural analytics queries , and ( 3 ) semi - structured queries . such queries could be specified using a high - level xml processing language such as xquery [ 6 ]. as discussed earlier , projection queries involve selecting nodes depend on a specified criteria . in accordance with at least one embodiment of the present invention , two main types of projection are enabled ; one type is based on the dimensional specification , while the other is based on the values of certain measurable features of the xml document . the scoped dimension descriptor ( 112 ) classifies dimensions into dependent and independent dimensions . the first projection approach selects all nodes that are spanned by a particular independent dimension and projects the xml tree without the selected nodes . this approach is called as hierarchical slicing . the selection criteria can be further refined by using xpath - based predicates [ see 6 ]. for example , the xml document illustrated in fig1 could be sliced along the employee dimension . the second approach involves selecting those nodes that are spanned by an dimension within a given scope . for example , the current xml document could be sliced along the department dimension that is spanned within another department dimension . this approach is called as hierarchical trimming . nodes could also be selected using a value - based selection criteria . values may be numeric , such as salary of employees , or non - numeric , such as names of employees . values can also measure certain structural features of the xml documents . for example , it can select only those employees whose organizational hierarchy contains two or more departments . this approach is called as hierarchical dicing . execution of such projection queries involves traversing the scoped dimension analysis model , choosing the node that represents the dimension , and then traversing the associated node list to select the nodes that need to be eliminated . the second class of queries concerns structural analytics , in particular , forecasting future trends that could be caused by possible changes in entity relationships . as an illustration , consider the example presented earlier , where an analyst wants to find out the impact of reorganization on a particular group &# 39 ; s budget . to implement such queries , the query processor ( 116 ) first creates a view of the analytical model to match the required structural change and re - assigns the node lists to their appropriate parent nodes . the query processor ( 116 ) then performs the necessary computation ( e . g ., budget computation ) on the new view . such structural analytics queries could be either written using a high - level xml query language such as xquery [ 6 ], or specified using a graphical tool . the scoped dimension analytical model is also suitable for answering queries that analyze semi - structured features of the xml document . for example , consider the clinical drug study example that studies the effect of a drug on a bio - metric parameter . suppose a researcher wants to study the effects of increased drug usage on a certain bio - metric parameter at regular intervals ( i . e ., after every 4 hours ). in this example , the increased drug usage could be first simulated using a structural forecasting technique . the order - based query could be then executed over the modified view . it is to be understood that the present invention , in accordance with at least one presently preferred embodiment , includes an arrangement for parsing an xml document by node , an arrangement for initializing the parsed node , an arrangement for storing values associated with the parsed node , and an arrangement for analyzing the parsed document . together , these elements may be implemented on at least one general - purpose computer running suitable software programs . they may also be implemented on at least one integrated circuit or part of at least one integrated circuit . thus , it is to be understood that the invention may be implemented in hardware , software , or a combination of both . if not otherwise stated herein , it is to be assumed that all patents , patent applications , patent publications and other publications ( including web - based publications ) mentioned and cited herein are hereby fully incorporated by reference herein as if set forth in their entirely herein . although illustrative embodiments of the present invention have been described herein with reference to the accompanying drawings , it is to be understood that the invention is not limited to those precise embodiments , and that various other changes and modifications may be affected therein by one skilled in the art without departing from the scope or spirit of the invention . 1 . d . barbara and m . sullivan , quasi - 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