Database extender for storing, querying, and retrieving structured documents

• US 6,584,459 B1
• Filed: 06/02/1999
• Issued: 06/24/2003
• Est. Priority Date: 10/08/1998
• Status: Expired due to Term

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Xu, Jian, Chow, Jyh-Herng, Chang, Daniel T., Cheng, Josephine M.
• Primary Examiner(s): Mizrahi, Diane D.
• Assistant Examiner(s): Mofiz, Apu M
• Application Number:
  US09/325,661
• Time in Patent Office: 1,483 Days
• Field of Search: 707/1, 707/2, 707/3, 707/4, 707/10, 707/100, 707/101, 707/104.1, 707/523, 709/219
• US Class Current: 707/812
• CPC Class Codes: G06F 16/284 Relational databases
• CPC Class Codes: G06F 16/93 Document management systems
• CPC Class Codes: Y10S 707/99933 Query processing, i.e. searching

Abstract

An extender for a computer-implemented relational database system is disclosed for storing, querying, and retrieving structured documents. The extender provides a new abstract data type and includes a plurality of user defined functions for storing, querying, and retrieving structured documents internally, as character-based large objects (CLOB), or externally, in flat files or URLs, for example.

A method and apparatus using an extender having a “conditional select” functionality is further disclosed for querying structured documents. The “conditional select” functionality is based on user defined functions residing within the extender being applied to a projection in a structured query in the database system.

A method and apparatus using an extender having a set of user defined functions is further disclosed for creating one or more indexes for structured documents stored in the relational database system. The method uses the set of functions to create the indexes and uses already created B+ tree index structures implemented in the database system to support the indexes.

A method and apparatus using an extender is further disclosed for creating and supporting structure indexes. The method includes a tag counting system for indexing structured documents and for implementing the structure indexes within the relational database.

Claims

1. A method of storing at least one structured document in a database system, using an extender for said database system, said extender enabling a user to store said at least one structured document in said database system, said method comprising the steps of:

defining a set of storing functions in said extender for processing said at least one structured document into a format having predefined attribute values; and

storing said at least one structured document in said database system using said storing functions.

2. The method according to claim 1, further comprising, prior to the step of defining said set of storing functions, the step of defining a data type in said database system for said at least one structured document.

3. The method according to claim 2, further comprising, subsequent to the step of defining said set of storing functions, the step of defining a table in said database system containing at least one column defined using said data type for said at least one structured document.

4. The method according to claim 3, further comprising, subsequent to the step of storing said at least one structured document, the step of updating said at least one column of said table in said database system.

5. The method according to claim 3, further comprising, subsequent to the step of storing said at least one structured document, the step of deleting said at least one column of said table in said database system.

6. The method according to claim 3, wherein said step of storing said at least one structured document in said database system further includes storing said at least one structured document in said at least one column of said table.

7. The method according to claim 1, further comprising, prior to the step of storing said at least one structured document, the step of defining and implementing an index structure based on characteristics input by said user.

8. The method according to claim 1, further comprising, subsequent to the step of defining a set of storing functions, the step of defining at least one reference table containing a plurality of document type definition elements of said at least one structured document.

9. The method according to claim 1, wherein said at least one structured document is written in Extensible Markup Language (XML).

10. The method according to claim 1, wherein said step of storing said at least one structured document in said database system further includes storing said at least one structured document in an external file system of said database system.

11. The method according to claim 1, wherein said step of storing said at least one structured document in said database system further includes storing a Uniform Resource Locator (URL) as a reference to said at least one structured document.

12. In a computer-based apparatus for storing at least one structured document in a database system, using an extender for said database system, said extender enabling a user to store said at least one structured document in said database system,

wherein said extender includes at least one facility for:

defining a set of storing functions in said extender for processing said at least one structured document into a format having predefined attribute values; and

storing said at least one structured document in said database system using said storing functions.

13. The apparatus according to claim 12, wherein said at least one facility of said extender, prior to defining said set of storing functions, further defines a data type in said database system for said at least one structured document.

14. The apparatus according to claim 13, wherein said at least one facility of said extender, subsequent to defining said set of storing functions, further defines a table in said database system containing at least one column defined using said data type for said at least one structured document.

15. The apparatus according to claim 14, wherein said at least one facility of said extender, subsequent to storing said at least one structured document, further updates said at least one column of said table in said database system.

16. The apparatus according to claim 14, wherein said at least one facility of said extender, subsequent to storing said at least one structured document, further deletes said at least one column of said table in said database system.

17. The apparatus according to claim 14, wherein said at least one facility of said extender, when storing said at least one structured document in said database system, further stores said at least one structured document in said at least one column of said table.

18. The apparatus according to claim 12, wherein said at least one facility of said extender, prior to storing said at least one structured document, further defines and implements an index structure based on characteristics input by said user.

19. The apparatus according to claim 12, wherein said at least one facility of said extender, subsequent to defining a set of storing functions, further defines at least one reference table containing a plurality of document type definition elements of said at least one structured document.

20. The apparatus according to claim 12, wherein said at least one structured document is written in Extensible Markup Language (XML).

21. The apparatus according to claim 12, wherein said at least one facility of said extender, when storing said at least one structured document in said database system, further stores said at least one structured document in an external file system of said database system.

22. The apparatus according to claim 12, wherein said at least one facility of said extender, when storing said at least one structured document in said database system, further stores a Uniform Resource Locator (URL) as a reference to said at least one structured document.

23. In an article of manufacture for storing at least one structured document in a database system, using an extender for said database system, said extender enabling a user to store said at least one structured document in said database system, said article of manufacture comprising a program storage medium readable by a computer, wherein said extender includes at least one facility for:

defining a set of storing functions in said extender for processing said at least one structured document into a format having predefined attribute values; and

storing said at least one structured document in said database system using said storing functions.

24. The article of manufacture according to claim 23, wherein said at least one facility of said extender, prior to defining said set of storing functions, further defines a data type in said database system for said at least one structured document.

25. The article of manufacture according to claim 24, wherein said at least one facility of said extender, subsequent to defining said set of storing functions, further defines a table in said database system containing at least one column defined using said data type for said at least one structured document.

26. The article of manufacture according to claim 25, wherein said at least one facility of said extender, subsequent to storing said at least one structured document, further updates said at least one column of said table in said database system.

27. The article of manufacture according to claim 25, wherein said at least one facility of said extender, subsequent to storing said at least one structured document, further deletes said at least one column of said table in said database system.

28. The article of manufacture according to claim 25, wherein said at least one facility of said extender, when storing said at least one structured document in said database system, further stores said at least one structured document in said at least one column of said table.

29. The article of manufacture according to claim 23, wherein said at least one facility of said extender, prior to storing said at least one structured document, further defines and implements an index structure based on characteristics input by said user.

30. The article of manufacture according to claim 23, wherein said at least one facility of said extender, subsequent to defining a set of functions, further defines at least one reference table containing a plurality of document type definition elements of said at least one structured document.

31. The article of manufacture according to claim 23, wherein said at least one structured document is written in Extensible Markup Language (XML).

32. The article of manufacture according to claim 23, wherein said at least one facility of said extender, when storing said at least one structured document in said database system, further stores said at least one structured document in an external file system of said database system.

33. The article of manufacture according to claim 23, wherein said at least one facility of said extender, when storing said at least one structured document in said database system, further stores a Uniform Resource Locator (URL) as a reference to said at least one structured document.

34. An extender for a database system for storing at least one structured document in said database system, said extender enabling a user to store said at least one structured document in said database system, said extender comprising:

a set of storing functions for processing said at least one structured document into a format having predefined attribute values, said storing functions residing in said extender;

said extender enabling said user to store said at least one structured document in said database system using said storing functions.

35. The extender according to claim 34, further comprising a data type for said at least one structured document, said data type residing in said database system.

36. The extender according to claim 35, further comprising a table residing in said database system and containing at least one column defined using said data type for said at least one structured document.

37. The extender according to claim 36, said extender enabling said user to update said at least one column of said table in said database system.

38. The extender according to claim 36, said extender enabling said user to delete said at least one column of said table in said database system.

39. The extender according to claim 36, said extender enabling said user to further store said at least one structured document in said at least one column of said table.

40. The extender according to claim 34, further comprising an index structure based on characteristics input by said user, said index structure being implemented in said database system for indexing said at least one structured document.

41. The extender according to claim 34, further comprising at least one reference table containing a plurality of document type definition elements of said at least one structured document.

42. The extender according to claim 34, wherein said at least one structured document is written in Extensible Markup Language (XML).

43. The extender according to claim 34, said extender enabling said user to further store said at least one structured document in an external file system of said database system.

44. The extender according to claim 34, said extender enabling said user to further store a Uniform Resource Locator (URL) as a reference to said at least one structured document.

45. A computer-readable storage medium storing an extender for a database system, said extender enabling a user to store at least one structured document in said database system, said extender comprising:

a set of storing functions for processing said at least one structured document into a format having predefined attribute values, said storing functions residing in said extender;

said extender enabling said user to store said at least one structured document in said database system using said storing functions.

46. The computer-readable storage medium according to claim 45, further comprising a data type for said at least one structured document, said data type residing in said database system.

47. The computer-readable storage medium according to claim 46, further comprising a table residing in said database system and containing at least one column defined using said data type for said at least one structured document.

48. The computer-readable storage medium according to claim 47, wherein said extender provides said user with access to further store said at least one structured document in said at least one column of said table.

49. The computer-readable storage medium according to claim 45, further comprising an index structure based on characteristics input by said user for indexing said at least one structured document.

50. The computer-readable storage medium according to claim 45, further comprising at least one reference table containing a plurality of document type definition elements of said at least one structured document.

51. The computer-readable storage medium according to claim 45, wherein said at least one structured document is written in Extensible Markup Language (XML).

52. The computer-readable storage medium according to claim 45, wherein said extender provides said user with access to further store said at least one structured document in an external file system of said database system.

53. The computer-readable storage medium according to claim 45, wherein said extender provides said user with access to further store a Uniform Resource Locator (URL) as a reference to said at least one structured document.

54. A method of executing a structured query given by a user in a database system, using an extender for said database system, said extender enabling a user to query said database system, said database system containing at least one structured document and having at least one data type for said at least one structured document, said database system further containing a table having at least one column defined using said at least one data type, said at least one column storing each of said at least one structured document, said method comprising the steps of:

defining a set of searching functions in said extender for executing said query; and

searching said at least one structured document in said at least one column of said table using said set of searching functions.

55. The method according to claim 54, wherein said at least one structured document is written in Extensible Markup Language (XML).

56. The method according to claim 54, wherein said at least one structured document is stored in an external file system of said database system.

57. The method according to claim 54, wherein a Uniform Resource Locator (URL) is stored in said database system as a reference to said at least one structured document.

58. In an apparatus for executing a structured query given by a user in a database system, using an extender for said database system, said extender enabling said user to query said database system, said database system containing at least one structured document and having at least one data type for said at least one structured document, said database system further containing a table having at least one column defined using said at least one data type, said at least one column storing each of said at least one structured document, said apparatus comprising a computer having at least one data storage device connected thereto, wherein said at least one data storage device stores said extender and said database system, and

wherein said extender includes at least one facility for:

defining a set of searching functions in said extender for executing said query; and

searching said at least one structured document in said at least one column of said table using said set of searching functions.

59. The apparatus according to claim 58, wherein said at least one structured document is written in Extensible Markup Language (XML).

60. The apparatus according to claim 58, wherein said at least one structured document is stored in an external file system of said database system.

61. The apparatus according to claim 58, wherein a Uniform Resource Locator (URL) is stored in said database system as a reference to said at least one structured document.

62. In an article of manufacture for executing a structured query given by a user in a database system, using an extender for said database system, said extender enabling said user to query said database system, said database system containing at least one structured document and having at least one data type for said at least one structured document, said database system further containing a table having at least one column defined using said at least one data type, said at least one column storing each of said at least one structured document, said article of manufacture comprising a program storage medium readable by a computer, wherein said extender includes at least one facility for:

defining a set of searching functions in said extender for executing said query; and

searching said at least one structured document in said at least one column of said table using said set of searching functions.

63. The article of manufacture according to claim 62, wherein said at least one structured document is written in Extensible Markup Language (XML).

64. The article of manufacture according to claim 62, wherein said at least one structured document is stored in an external file system of said database system.

65. The article of manufacture according to claim 62, wherein a Uniform Resource Locator (URL) is stored in said database system as a reference to said at least one structured document.

66. An extender for a database system for executing a structured query given by a user in a database system, said extender enabling said user to query said database system, said database system containing at least one structured document and having at least one data type for said at least one structured document, said database system further containing a table having at least one column defined using said at least one data type, said at least one column storing each of said at least one structured document, said extender comprising at least one facility for:

defining a set of searching functions in said extender for executing said query; and

searching said at least one structured document in said at least one column of said table using said set of searching functions.

67. The extender according to claim 66, wherein said at least one structured document is written in Extensible Markup Language (XML).

68. The extender according to claim 66, wherein said at least one structured document is stored in an external file system of said database system.

69. The extender according to claim 66, wherein a Uniform Resource Locator (URL) is stored in said database system as a reference to said at least one structured document.

70. A computer-readable storage medium storing an extender for a database system, said extender enabling a user to query at least one structured document in said database system, wherein said extender defines and implements new complex data types, including storing the attributes, structure, and behavior of the data types in a column of a relational database table;

and wherein the complex data types are defined and implemented so as to either support new applications to be run or extend existing business applications, said extender comprising;

a set of searching functions for executing a structured query given by a user in a database system, said searching functions residing in said extender;

said extender enabling said user to query said at least one structured document in said database system using said searching functions.

71. The computer-readable storage medium according to claim 70, wherein said data types comprise a data type for said at least one structured document, said data type residing in said database system.

72. The computer-readable storage medium according to claim 71, wherein said table contains at least one of said column defined using said data type for said at least one structured document, and said at least one column stores each of said at least one structured document.

73. The computer-readable storage medium according to claim 70, wherein said at least one structured document is written in Extensible Markup Language (XML).

74. The computer-readable storage medium according to claim 70, wherein said at least one structured document is stored in an external file system of said database system.

75. The computer-readable storage medium according to claim 70, wherein a Uniform Resource Locator (URL) is stored in said database system as a reference to said at least one structured document.

76. A method of retrieving at least one structured document from a database system, using an extender for said database system, said extender enabling a user to retrieve said at least one structured document, said database system containing said at least one structured document and having at least one data type for said at least one structured document, said database system further containing a table having at least one column defined using said at least one data type, said at least one column storing each of said at least one structured document, said method comprising the steps of:

defining a set of retrieval functions in said extender; and

retrieving said at least one structured document from said at least one column of said table using said set of retrieval functions.

77. The method according to claim 76, wherein said at least one structured document is written in Extensible Markup Language (XML).

78. The method according to claim 76, wherein said at least one structured document is stored in an external file system of said database system.

79. The method according to claim 76, wherein a Uniform Resource Locator (URL) is stored in said database system as a reference to said at least one structured document.

80. In a computer-based apparatus for retrieving at least one structured document from a database system, using an extender for said database system, said extender enabling a user to retrieve said at least one structured document, said database system containing at least one structured document and having at least one data type for said at least one structured document, said database system further containing a table having at least one column defined using said at least one data type, said at least one column storing each of said at least one structured document, said apparatus comprising a computer having at least one data storage device connected thereto, wherein said at least one data storage device stores said extender and said database system, and

wherein said extender includes at least one facility for:

defining a set of retrieval functions in said extender; and

retrieving said at least one structured document in said at least one column of said table using said set of retrieval functions.

81. The apparatus according to claim 80, wherein said at least one structured document is written in Extensible Markup Language (XML).

82. The apparatus according to claim 80, wherein said at least one structured document is stored in an external file system of said database system.

83. The apparatus according to claim 80, wherein a Uniform Resource Locator (URL) is stored in said database system as a reference to said at least one structured document.

84. In an article of manufacture for retrieving at least one structured document from a database system, using an extender for said database system, said extender enabling a user to retrieve said at least one structured document, said database system containing at least one structured document and having at least one data type for said at least one structured document, said database system further containing a table having at least one column defined using said at least one data type, said at least one column storing each of said at least one structured document, said article of manufacture comprising a program storage medium readable by a computer, wherein said extender includes at least one facility for:

defining a set of retrieval functions in said extender; and

retrieving said at least one structured document in said at least one column of said table using said set of retrieval functions.

85. The article of manufacture according to claim 84, wherein said at least one structured document is written in Extensible Markup Language (XML).

86. The article of manufacture according to claim 84, wherein said at least one structured document is stored in an external file system of said database system.

87. The article of manufacture according to claim 84, wherein a Uniform Resource Locator (URL) is stored in said database system as a reference to said at least one structured document.

88. An extender for a database system for retrieving at least one structured document from a database system, said extender enabling a user to retrieve said at least one structured document, said database system containing at least one structured document and having at least one data type for said at least one structured document, said database system further containing a table having at least one column defined using said at least one data type, said at least one column storing each of said at least one structured document, said extender comprising at least one facility for:

defining a set of retrieval functions in said extender; and

retrieving said at least one structured document in said at least one column of said table using said set of retrieval functions.

89. The extender according to claim 88, wherein said at least one structured document is written in Extensible Markup Language (XML).

90. The extender according to claim 88, wherein said at least one structured document is stored in an external file system of said database system.

91. The extender according to claim 88, wherein a Uniform Resource Locator (URL) is stored in said database system as a reference to said at least one structured document.

92. A computer-readable storage medium storing an extender for a database system, said extender enabling a user to retrieve at least one structured document from said database system, wherein said extender defines and implements new complex data types, including storing the attributes, structure, and behavior of the data types in a column of a relational database table;

and wherein the complex data types are defined and implemented so as to either support new applications to be run or extend existing business applications, said extender comprising;

a set of retrieval functions residing in said extender;

said extender enabling said user to retrieve said at least one structured document in said database system using said retrieval functions.

93. The computer-readable storage medium according to claim 92, wherein said data types comprise a data type for said at least one structured document, said data type residing in said database system.

94. The computer-readable storage medium according to claim 93, wherein said table contains at least one of said column defined using said data type for said at least one structured document, and said at least one column stores each of said at least one structured document.

95. The computer-readable storage medium according to claim 92, wherein said at least one structured document is written in Extensible Markup Language (XML).

96. The computer-readable storage medium according to claim 92, wherein said at least one structured document is stored in an external file system of said database system.

97. The computer-readable storage medium according to claim 92, wherein a Uniform Resource Locator (URL) is stored in said database system as a reference to said at least one structured document.