Federated query management

• US 20040103088A1
• Filed: 11/27/2002
• Published: 05/27/2004
• Est. Priority Date: 11/27/2002
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Wall, David A., Fish, Douglas R., Rath, Cale T., Cragun, Brian J.
• Granted Patent: US 7,243,093 B2
• Time in Patent Office: Days
• US Class Current: 707/3
• CPC Class Codes: G06F 16/2471 Distributed queries
• CPC Class Codes: G06F 16/256 in federated or virtual databases
• CPC Class Codes: Y10S 707/99931 Database or file accessing
• CPC Class Codes: Y10S 707/99932 Access augmentation or optimizing
• CPC Class Codes: Y10S 707/99933 Query processing, i.e. searching
• CPC Class Codes: Y10S 707/99934 Query formulation, input preparation, or translation
• CPC Class Codes: Y10S 707/99935 Query augmenting and refining, e.g. inexact access

Abstract

Embodiments of the present invention generally provide a system, method and article of manufacture for managing federated queries. In general, the availability of one or more databases targeted by a federated query may be determined prior to running the federated query against the targeted databases. In response to determining one or more of the targeted databases are unavailable, a user may be notified. The user may also be presented with options for running the federated query. The options may include being notified when all of the targeted databases are available, automatically running the federated query (in the background) when all of the targeted databases are available, and modifying the query to run against currently available databases.

Claims

1. A method for accessing data in a federated database system, comprising:

receiving, from a user, a federated query targeting one or more databases; and

determining the availability of the targeted databases prior to executing the query.

2. The method of claim 1, wherein determining the availability of the targeted databases comprises executing a query against each of the targeted databases.

3. The method of claim 1, wherein determining the availability of the targeted databases comprises determining the availability of each database in the federated database system.

4. The method of claim 1, further comprising:

receiving, from the user, a selected option for executing the federated query; and

executing the query according to the user selected option.

5. The method of claim 4, wherein the selected option for executing the federated query is one of automatically executing the federated query when all of the targeted databases become available and modifying the federated query to run against available databases.

6. The method of claim 5, wherein modifying the federated query to run against available databases comprises modifying the federated query to run against a backup database of an unavailable targeted database.

7. The method of claim 4, further comprising, in response to determining one or more of the targeted databases is not available, presenting the user with options for executing the federated query.

8. A method for accessing data, comprising:

presenting, to a user, a list of federated queries targeting one or more databases;

determining the availability of the targeted databases; and

indicating, to the user, which of the listed federated queries, if executed, should return valid results, based on the determined availability of the targeted databases.

9. The method of claim 8, wherein determining the availability of the targeted databases comprises executing a query against each of the targeted databases.

10. The method of claim 8, further comprising:

receiving, from the user, a selected one of the listed federated queries; and

presenting, to the user, options for executing the selected federated query in response to determining one or more of the databases targeted by the selected federated query are unavailable.

11. The method of claim 10, wherein the options for executing the selected federated query include at least one of:

automatically executing the query when all of databases targeted by the selected federated query become available;

notifying the user when all of databases targeted by the selected federated query become available; and

modifying to execute against available databases.

12. The method of claim 11, further comprising receiving a user selected one of the options and executing the federating query according to the user selected option.

13. A method comprising:

generating a federated query targeting one or more databases; and

saving the federated query with a list of the targeted databases in a federated query database.

14. The method of claim 13, further comprising transforming the federated query from a query consistent with a first data representation to a query consistent with a second data representation.

15. The method of claim 14, wherein the second data representation is XML.

16. The method of claim 15, further comprising:

retrieving the federated query from the federated query database;

determining availability of the targeted databases; and

if any of the targeted databases are unavailable, notifying a user.

17. The method of claim 16, further comprising, if all of the targeted databases are available:

parsing the federated query into subqueries to run against one of the targeted databases;

converting at least one of the subqueries from XML to a subquery consistent with a data representation associated with the database targeted by the subquery; and

executing the subqueries.

18. A computer-readable medium containing a program which, when executed by a processor, performs operations comprising:

receiving, from a user, a federated query targeting one or more databases;

determining availability of the targeted databases prior to executing the federated query; and

notifying the user in response to determining one or more of the targeted databases is not available.

19. The computer-readable medium of claim 18, wherein the operations further comprise providing the user one or more graphical user interface (GUI) screens for generating the federated query.

20. The computer-readable medium of claim 19, wherein providing the user one or more GUI screens for generating the federated query comprises providing one or more GUI screens presenting the user with a list of previously saved federated queries.

21. The computer-readable medium of claim 20, wherein the operations further comprise indicating which of the previously saved federated queries will run based on availability of databases targeted by the previously saved federated queries.

22. The computer-readable medium of claim 21, further comprising:

receiving, from the user, a selected one of the previously saved federated queries to run;

in response to determining one or more databases targeted by the selected federated query are not available, providing the user with options for running the selected federated query; and

running the selected federated query according to a user selected one of the options.

23. The computer-readable medium of claim 19, wherein providing the user one or more GUI screens for generating the federated query comprises:

providing one or more GUI screens allowing the user to specify query conditions based on fields, wherein each field is associated with at least one of the targeted databases; and

indicating which of the fields, if any, are associated with an unavailable database.

24. A federated database system, comprising:

a query building interface allowing a user to specify a federated query targeting one or more databases; and

a federated query manager configured to receive the federated query from the query building interface, determine the availability of the targeted databases, and notify the query building interface in response to determining one or more of the targeted databases are unavailable.

25. The federated database system of claim 24, wherein the query building interface is further configured to present the user with options for running the federated query in response to receiving notification from the federated query manager that one or more of the targeted databases are unavailable.

26. The federated database system of claim 25, wherein the options for running the federated query include at least one of:

automatically running the federated query when all of the targeted databases become available;

receiving notification when all of the targeted databases become available; and

modifying the query to run against available databases.

27. The federated database system of claim 26, wherein modifying the query to run against the available databases comprises automatically modifying the query by the federated query manager.

28. The federated database system of claim 24, wherein the query building interface is configured to:

present, to the user, a list of federated queries; and

indicate, to the user, which of the listed federated queries will run based on information received from the federated query manager regarding availability of databases targeted by the listed federated queries.

29. The federated database system of claim 24, wherein the query building interface is further configured to:

receive, from the user, a selected one of the listed federated queries; and

in response to determining the selected federated query will not run, based on information received from the federated query manager regarding availability of databases targeted by the selected federated query, present the user with options for running the selected query.

30. The federated database system of claim 24, wherein the federated query manager is configured to parse the federated query into subqueries, each targeting a different one of the targeted databases, and the federated database system further comprises query format translator configured to translate at least one of the subqueries from a subquery consistent with a first physical data format to a subquery consistent with a second physical data format.