Techniques for efficient loading of binary XML data

• US 8,010,889 B2
• Filed: 05/02/2007
• Issued: 08/30/2011
• Est. Priority Date: 10/20/2006
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle International Corporation (Oracle Corporation)
• Inventors: Gupta, Nitin, Chandrasekar, Sivasankaran, Murthy, Ravi, Agarwal, Nipun
• Primary Examiner(s): Stork; Kyle R
• Application Number:
  US11/743,563
• Publication Number:
  US 20080098001A1
• Time in Patent Office: 1,581 Days
• Field of Search: 715/234, 715/235, 715/236, 715/243, 715/254
• US Class Current: 715/234
• CPC Class Codes: G06F 16/258 Data format conversion from or to a database
• CPC Class Codes: G06F 16/80 of semi-structured data, e.g. markup language structured data such as SGML, XML or HTML content-based retrieval of web data G06F16/95
• CPC Class Codes: H03M 7/30 Compression speech analysis-synthesis for redundancy reduction G10L19/00; for image communication H04N; Expansion; Suppression of unnecessary data, e.g. redundancy reduction

Abstract

Various techniques are described hereafter for improving the efficiency of binary XML encoding and loading operations. In particular, techniques are described for incrementally encoding XML in response to amount-based requests. After encoding enough binary XML to satisfy an amount-based request, the encoder stops encoding the XML until a subsequent request is received. The incremental encoding may take place on the client-side or the server-side. Techniques are also described for reducing the character set conversion operations by having a parser convert tokens in text XML into one character set while converting non-token text in the text XML into another character set. Techniques are also described for generating self-contained binary XML documents, and for improving remap operations by providing a binary XML document on a chunk-by-chunk basis.

Claims

1. A method for encoding a particular text XML, comprising the computer-implemented steps of:

receiving a request for a first specified amount of binary encoded XML, wherein the first specified amount is less than the entire amount that would be produced by encoding the entire particular text XML, and wherein the first specified amount is a numerical value that communicates a size that equates to a particular number of bytes;

in response to the request, encoding one or more nodes from the particular text XML on a per-node basis until a first amount of binary XML, which has been generated to satisfy the request, is equal to or greater than the first specified amount;

responding to the request with a second amount of binary XML, wherein the second amount of binary XML is not greater than the first specified amount;

once the request has been satisfied, ceasing to encode the particular text XML until receiving a subsequent request for binary encoded XML;

receiving the subsequent request for a second specified amount of binary encoded XML;

in response to the subsequent request, continuing to encode the particular text XML from a node that is subsequent to the one or more nodes that were used to generate the first amount of binary XML; and

responding to the subsequent request with a third amount of binary XML, wherein the third amount of binary XML is not greater than the second specified amount;

wherein the steps of the method are performed by one or more computer systems.

2. The method of claim 1, wherein:

the first amount of binary XML exceeds the first specified amount by a fourth amount of binary XML; and

the method further includes;

storing the fourth amount of binary XML in a carry-over buffer until receiving the subsequent request for binary encoded XML; and

using said fourth amount of binary XML to satisfy said subsequent request for binary encoded XML.

3. The method of claim 2, wherein the second specified amount is greater than said fourth amount of binary XML, and wherein continuing to encode the particular text XML further comprises:

determining a difference between the second specified amount and said fourth amount of binary XML;

encoding the particular text XML to produce a portion of binary XML that is greater than said difference; and

including, in the third amount of binary XML, the portion of binary XML and said fourth amount of binary XML.

4. The method of claim 1 wherein the step of encoding the particular text XML is performed at a database server that stores the binary XML in an XML repository.

5. The method of claim 1 wherein:

the step of encoding the particular text XML is performed at a client, and

the request is from a database server that manages an XML repository.

6. The method of claim 5 wherein the database server repeatedly sends the client requests for specific amounts of binary XML, and loads the binary XML that the database server receives in response to the requests directly into a structure within the database repository without buffering a copy of the binary XML.

7. A non-transitory computer-readable storage medium storing one or more sequences of instructions which, when executed by one or more processors, cause the one or more processors to perform steps comprising:

receiving a request for a first specified amount of binary encoded XML, wherein the first specified amount is less than the entire amount that would be produced by encoding the entire particular text XML, and wherein the first specified amount is a numerical value that communicates a size that equates to a particular number of bytes;

in response to the request, encoding one or more nodes from the particular text XML on a per-node basis until a first amount of binary XML, which has been generated to satisfy the request, is equal to or greater than the first specified amount;

responding to the request with a second amount of binary XML, wherein the second amount of binary XML is not greater than the first specified amount;

once the request has been satisfied, ceasing to encode the particular text XML until receiving a subsequent request for binary encoded XML;

receiving the subsequent request for a second specified amount of binary encoded XML;

in response to the subsequent request, continuing to encode the particular text XML from a node that is subsequent to the one or more nodes that were used to generate the first amount of binary XML; and

responding to the subsequent request with a third amount of binary XML, wherein the third amount of binary XML is not greater than the second specified amount.

8. The non-transitory computer-readable storage medium of claim 7, wherein:

the first amount of binary XML exceeds the first specified amount by a fourth amount of binary XML; and

the one or more sequences of instructions further comprise instructions which, when executed by the one or more processors, cause the one or more processors to perform the steps of;

storing the fourth amount of binary XML in a carry-over buffer until receiving the subsequent request for binary encoded XML; and

using said fourth amount of binary XML to satisfy said subsequent request for binary encoded XML.

9. The non-transitory computer-readable storage medium of claim 8, wherein the second specified amount is greater than said fourth amount of binary XML, and wherein the instructions that cause continuing to encode the particular text XML further comprise instructions which, when executed by the one or more processors, cause the one or more processors to perform the steps of:

determining a difference between the second specified amount and said fourth amount of binary XML;

encoding the particular text XML to produce a portion of binary XML that is greater than said difference; and

including, in the third amount of binary XML, the portion of binary XML and said fourth amount of binary XML.

10. The non-transitory computer-readable storage medium of claim 7, wherein the instructions that cause encoding the particular text XML are included in a set of instructions of a database server that stores the binary XML in an XML repository.

11. The non-transitory computer-readable storage medium of claim 7, wherein:

the instructions that cause encoding the particular text XML are included in a set of instructions of a client, and

the request is from a database server that manages an XML repository.

12. The non-transitory computer-readable storage medium of claim 11, wherein the database server repeatedly sends the client requests for specific amounts of binary XML, and loads the binary XML that the database server receives in response to the requests directly into a structure within the database repository without buffering a copy of the binary XML.