Method to provide management of query output

• US 7,844,623 B2
• Filed: 01/22/2008
• Issued: 11/30/2010
• Est. Priority Date: 06/17/2004
• Status: Expired due to Fees

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Johnson, Peter J., Dettinger, Richard D., Wenzel, Shannon E., Kolz, Dan P.
• Primary Examiner(s): Wong; Leslie
• Application Number:
  US12/017,373
• Publication Number:
  US 20080140612A1
• Time in Patent Office: 1,043 Days
• Field of Search: 707/999.003, 707/999.004, 707/999.107, 707/764, 707/770
• US Class Current: 707/770
• CPC Class Codes: G06F 16/242 Query formulation
• CPC Class Codes: G06F 16/2452 Query translation
• CPC Class Codes: G06F 16/248 Presentation of query results
• 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
• CPC Class Codes: Y10S 707/99945 Object-oriented database structure processing

Abstract

System and article of manufacture for processing queries that are executed against a database. In one embodiment, the database environment imposes a limit on the number of columns capable of being returned for a single query. Accordingly, a single query is replicated to produce N sub-queries, each selecting a portion of the total number of result fields specified in the single query.

Claims

1. A computer-readable storage medium containing a program which, when executed by a processor, performs an operation of processing or managing query executions against a database, the operation comprising:

receiving, from a requesting entity, a query comprising a plurality of result fields to be returned following execution of the query;

determining whether the number of the plurality of result fields exceeds a maximum number of columns capable of being returned for a single query; and

if so;

creating a plurality of sub-queries, wherein each sub-query includes only a portion of the result fields, not greater than the maximum number of columns capable of being returned, and wherein the portions collectively include all of the result fields of the query;

executing the plurality of sub-queries in lieu of the query;

receiving a separate result set for each of the sub-queries;

returning the results to the requesting entity; and

mapping the separate result set for each of the sub-queries to a singular output view for presentation to a user; and

if not;

executing the query as received from the requesting entity; and

returning the results to the requesting entity.

2. The computer-readable storage medium of claim 1, wherein N sub-queries are created and wherein the number of result fields in each portion of at least N−

1 sub-queries is exactly equal to the maximum number of columns capable of being returned for a single query, wherein N is an integer.

3. The computer-readable storage medium of claim 1, wherein the query specifies two or more tables from which the plurality of result sets is to be retrieved and further comprising:

creating at least one of the plurality of sub-queries on the basis of table boundaries of the one of the two or more tables, whereby the at least one of the plurality of sub-queries specifies selection of result fields from only one of the two or more tables.

4. The computer-readable storage medium of claim 1, wherein the operation further comprises:

mapping each result field of the separate result set to a separate column of an output view for presentation to a user.

5. The computer-readable storage medium of claim 1, wherein the operation further comprises:

mapping each result field of the separate result set to a separate column of an output view for presentation to a user according to an order of the plurality of result fields in the query.

6. The computer-readable storage medium of claim 1, wherein the operation further comprises:

creating an index that maps each result field of the separate result sets to an output field of a view for presentation to a user, whereby the view includes each of the plurality of result fields of the query.

7. A computer-readable storage medium containing a program which, when executed by a processor, performs a process for processing or managing query executions against a database, the process comprising:

receiving an abstract query including at least a plurality of result fields, each corresponding to a logical field definition of a data abstraction model abstractly describing the data in the database;

determining whether the number of the plurality of result fields exceeds a maximum number of columns capable of being returned for a single query;

if so;

creating a plurality of sub-queries, wherein each sub-query includes only a portion of the result fields, not greater than the maximum number of columns capable of being returned, and wherein the portions collectively include all of the result fields of the query;

executing the plurality of sub-queries in lieu of the query;

receiving a separate result set for each of the sub-queries;

returning the results to the requesting entity; and

mapping the separate result set for each of the sub-queries to a singular output view for presentation to a user; and

if not;

executing the query as received from the requesting entity; and

returning the results to the requesting entity.

8. The computer-readable storage medium of claim 7, wherein the process further comprises:

transforming the abstract query into an executable query for execution against the data in the database.

9. The computer-readable storage medium of claim 7, wherein the executable query is an SQL query.

10. The computer-readable storage medium of claim 7, wherein creating the plurality of sub-queries is done after transforming the abstract query into the executable query.

11. A computer, comprising:

one or more processors;

a user interface for composing queries;

a query manager, which when executed by one or more of the processors, is configured to;

receive a query composed in the user interface and comprising a plurality of result fields to be returned following execution of the query;

determine whether the number of the plurality of result fields exceeds a maximum number of columns capable of being returned for a single query;

if so;

create a plurality of sub-queries, wherein each sub-query includes only a portion of the result fields, not greater than the maximum number of columns capable of being returned, and wherein the portions collectively include all of the result fields of the query;

execute the plurality of sub-queries in lieu of the query;

receive a separate result set for each of the sub-queries; and

return the results to a requesting entity; and

if not;

execute the query as received from the requesting entity; and

return the results to the requesting entity; and

a mapping algorithm, which when executed by one or more of the processors, is configured to map the separate result set for each of the sub-queries to a singular output view for presentation to a user.