Method and mechanism for loading XML documents into memory

• US 7,933,928 B2
• Filed: 12/22/2005
• Issued: 04/26/2011
• Est. Priority Date: 12/22/2005
• Status: Active Grant

• Current Assignee: Oracle International Corporation (Oracle Corporation)
• Original Assignee: Oracle International Corporation (Oracle Corporation)
• Inventors: Jain, Namit, Chandrasekar, Sivasankaran, Murthy, Ravi, Agarwal, Nipun
• Primary Examiner(s): Ali; Mohammad
• Assistant Examiner(s): Corbo; Griselle
• Application Number:
  US11/317,101
• Publication Number:
  US 20070150432A1
• Time in Patent Office: 1,951 Days
• Field of Search: 707/1, 707/E17.127, 707/802, 707/821, 707/999.001
• US Class Current: 707/802
• 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: G06F 40/143 Markup, e.g. Standard Generalized Markup Language [SGML] or Document Type Definition [DTD]

Abstract

A method and apparatus for loading an XML document into memory is provided. A client loads one or more array elements into a first partition of an array that is maintained in memory. Each array element represents an XML element of an XML document. Upon determining that an amount of data maintained in the first partition exceeds a first threshold, the client subsequently loads array elements into a new partition of the array. Upon determining that an amount of data maintained in the memory of the client exceeds a second threshold, the array elements of the least recently used partition are persistently stored in a database without persistently storing the entire XML document. When the last XML element of the XML document is loaded into a partition of the array, that partition is persistently stored in the database, thereby causing the entire XML document to be stored in the database.

Claims

1. A method for storing a single XML document in multiple database data blocks of a database, comprising:

at a client, storing data representing at least one XML element in a first partition of an array maintained in client memory of the client, said at least one XML element corresponding to only part of an XML document;

wherein the array is populated by array elements of a first XML type;

upon determining that a first amount of data maintained in the first partition exceeds a partition size threshold, (a) creating a new partition of the array, in the client memory, that is different and other than the first partition, and (b) subsequently loading the array elements of the first XML type into the new partition of the array;

upon determining that a second amount of data maintained in the client memory exceeds a client memory size threshold, transmitting a request to a database server of said database to store data in the first partition in a database data block of said database;

transmitting a second request to said database server to store data in the new partition in a database data block of said database;

wherein transmitting a request to a database server of said database to store data in the first partition in a database data block and transmitting a request to said database server to store data in the second partition in a database data block cause the data for the first partition and data for the new partition to be stored in separate and distinct data blocks of said database; and

wherein the method is performed by one or more computing devices.

2. The method of claim 1, further comprising determining a size of said new partition based on, at least in part, (a) available memory of the client or (b) a location within the database where the array elements of said new partition are to be stored.

3. The method of claim 1, further comprising determining a size of said new partition based on, at least in part, a number of repeating XML elements within said XML document.

4. The method of claim 1, wherein said request specifies to store a data stream that conforms to a data block format of said database managed by said database server.

5. The method of claim 1, wherein the request to said database server to store said data in the first partition in a database is a request to persistently store second array elements of the first partition in said database using a single batch INSERT SQL operation.

6. The method of claim 1, further comprising determining that the first partition is a least recently partition in a set of partitions maintained in the client memory of the client.

7. The method of claim 1,

further comprising, after storing second array elements of the first partition in said database, ceasing to maintain the first partition in the client memory of the client.

8. A method for storing a single XML document in multiple database data blocks of a database, comprising:

at a client, loading one or more first array elements into a first partition of an array maintained in client memory of the client, wherein each array element, of the one or more first array elements, represents an XML element of an XML document;

wherein the array is populated by a plurality of array elements of a first XML type;

upon determining that a first amount of data maintained in the first partition exceeds a partition size threshold, (a) creating a new partition of the array, in the client memory, that is different and other than the first partition, and (b) subsequently loading the plurality of array elements of the first XML type into the new partition of the array;

upon determining that a second amount of data maintained in the client memory exceeds a client memory size threshold, persistently storing the first array elements, of the first partition, in said database without persistently storing the entire XML document;

transmitting a request to a database server of said database to store data in the new partition in a database data block of said database;

wherein transmitting a request to a database server to store data in the first partition in a database data block and persistently storing the first array elements, of the first partition, in said database without persistently storing the entire XML document cause the data for the first partition and data for the new partition to be stored in separate and distinct data blocks of said database; and

wherein the method is performed by one or more computing devices.

9. A volatile or non-volatile machine-readable medium carrying instructions, wherein the instructions, when executed by one or more processors, cause the one or more processors to perform the steps of:

at a client, storing data representing at least one XML element in a first partition of an array maintained in client memory of the client, said at least one XML element corresponding to only part of an XML document;

wherein the array is populated by array elements of a first XML type;

upon determining that a first amount of data maintained in the first partition exceeds a partition size threshold, (a) creating a new partition of the array, in the client memory, that is different and other than the first partition, and (b) subsequently loading the array elements of the first XML type into the new partition of the array;

upon determining that a second amount of data maintained in the client memory exceeds a client memory size threshold, transmitting a request to a database server of said database to store data in the first partition in a database data block of said database;

transmitting a second request to said database server to store data in the new partition in a database data block of said database;

wherein transmitting a request to a database server of said database to store data in the first partition in a database data block and transmitting a request to said database server to store data in the second partition in a database data block cause the data for the first partition and data for the new partition to be stored in separate and distinct data blocks of said database.

10. The medium of claim 9, wherein the instructions further comprise instructions, when executed by the one or more processors, cause the one or more processors to perform determining a size of said new partition based on, at least in part, (a) available memory of the client or (b) a location within the database where the array elements of said new partition are to be stored.

11. The medium of claim 9, wherein the instructions further comprise instructions, when executed by the one or more processors, cause the one or more processors to perform determining a size of said new partition based on, at least in part, a number of repeating XML elements within said XML document.

12. The medium of claim 9, wherein said request specifies to store a data stream that conforms to data block format of the database managed by said database server.

13. The medium of claim 9, wherein the request to said database server to store said data in the first partition in the database is a request to persistently store second array elements of the first partition in a database using a single batch INSERT SQL operation.

14. The medium of claim 9, wherein the instructions further comprise instructions, when executed by the one or more processors, cause the one or more processors to perform determining that the first partition is a least recently partition in a set of partitions maintained in the client memory of the client.

15. The medium of claim 9, wherein the instructions further comprise instructions, when executed by the one or more processors, cause the one or more processors to perform, after storing second array elements of the first partition in the database, ceasing to maintain the first partition in the client memory of the client.