Technique For Skipping Irrelevant Portions Of Documents During Streaming XPath Evaluation

• US 20140215311A1
• Filed: 03/31/2014
• Published: 07/31/2014
• Est. Priority Date: 06/25/2009
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle International Corporation (Oracle Corporation)
• Inventors: Idicula, Sam, Agarwal, Nipun, Malde, Sanket
• Granted Patent: US 10,037,311 B2
• Time in Patent Office: Days
• US Class Current: 715/234
• CPC Class Codes: G06F 16/835 Query processing
• CPC Class Codes: G06F 40/12 Use of codes for handling textual entities
• CPC Class Codes: G06F 40/143 Markup, e.g. Standard Generalized Markup Language [SGML] or Document Type Definition [DTD]

Abstract

A method and apparatus are described for summarizing a document. For each node in the document that satisfies a marking criteria, a start and end mark pair is stored in a summary in document order. The start mark specifies a location in the document where the node starts, and the end mark specifies a location in the document where the node ends. When evaluating a query for a hierarchical path, the document is streamed into memory until the mark of a tag matches a start mark in the summary. If that tag does not fit within the path, then streaming of the document may resume at the end mark, thereby skipping the node during streaming evaluation. Translation information may be used to indicate a logical position relative to the marks in the summary when the document is modified.

Claims

1. A method for summarizing a document comprising nodes of hierarchical markup data, the method comprising:

for each node of the nodes, determining, by one or more computing devices, whether the node satisfies one or more marking criteria;

for each node that satisfies the one or more marking criteria, generating, by the one or more computing devices, a pair of marks for the node, the pair comprising a start mark and an end mark for the node, the start mark specifying a first location in the document where the node starts, and the end mark specifying a second location in the document that is at or after where the node ends; and

storing the pairs of marks ordered based at least in part on the start mark.

2. The method of claim 1, wherein the one or more marking criteria is a size of the node.

3. The method of claim 1, wherein the one or more marking criteria is a number of subnodes of the node.

4. The method of claim 1, wherein the one or more marking criteria is a name of the node and sub-nodes.

5. The method of claim 1, wherein the one or more marking criteria is a value of the node and sub-nodes.

6. The method of claim 1, wherein the storing the pairs of marks ordered based at least in part on the start mark comprises:

storing the pairs of marks in the order that the start marks of the pairs appear in the document.

7. The method of claim 1, wherein the document comprising nodes of hierarchical markup data is a plurality of documents comprising nodes of hierarchical markup data.

8. A method for storing metadata for a document, the method comprising:

in a summary, storing marks for nodes of the document that satisfy one or more marking criteria, the marks comprising start marks and end marks, the start marks specifying first locations in the document where nodes start, and the end marks specifying second locations in the document at or after where nodes end;

determining that one or more modifications have been made to a set of nodes in the document;

based at least in part on the one or more modifications, storing a logical value relative to at least one of the marks stored in the summary.

11. The method of claim 8, further comprising:

determining that one or more nodes of the set of nodes satisfies one or more marking criteria;

determining that the summary does not include marks for the one or more nodes of the set of nodes;

adding marks to a new position in the summary for the one or more nodes; and

storing a logical position that indicates a position relative to the new position of the added marks.

12. The method of claim 8, further comprising:

determining that one or more nodes of the set of nodes does not satisfy one or more marking criteria;

determining that the summary includes marks for the one or more nodes of the set of nodes;

deleting marks from the summary for the one or more nodes.

13. The method of claim 8, wherein the document is one or more documents that conform to a hierarchical markup language.

14. One or more non-transitory computer-readable storage medium storing one or more sequences of instruction, wherein execution of the one or more sequences of instruction by one or more processors causes the one or more processors to perform:

reading a document comprising nodes of hierarchical markup data;

for each node of the nodes, determining, by one or more computing devices, whether the node satisfies one or more marking criteria;

for each node that satisfies the one or more marking criteria, generating, by the one or more computing devices, a pair of marks for the node, the pair comprising a start mark and an end mark for the node, the start mark specifying a first location in the document where the node starts, and the end mark specifying a second location in the document that is at or after where the node ends; and

storing the pairs of marks ordered based at least in part on the start mark

15. One or more non-transitory computer-readable storage medium storing one or more sequences of instruction, wherein execution of the one or more sequences of instruction by one or more processors causes the one or more processors to perform:

in a summary, storing marks for nodes in a document that satisfy one or more marking criteria, the marks comprising start marks and end marks, the start marks specifying first locations in the document where nodes start, and the end marks specifying second locations in the document at or after where nodes end;

determining that one or more modifications have been made to a set of nodes in the document;

based at least in part on the one or more modifications, storing a logical value relative to at least one of the marks stored in the summary.

9. The method of claim 15, wherein the one or more modifications include adding data to the set of nodes in the document, and wherein the logical value indicates a positive value relative to the at least one of the marks.

10. The method of claim 15, wherein the one or more modifications include deleting data from the set of nodes in the document, and wherein the logical value indicates a negative value relative to the at least one of the marks.