Providing efficient access to redundant number representations

• US 8,548,984 B2
• Filed: 02/14/2012
• Issued: 10/01/2013
• Est. Priority Date: 01/14/2005
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Ricard, Gary Ross, Schmidt, William Jon
• Primary Examiner(s): Pulliam, Christyann
• Assistant Examiner(s): Khoshnoodi, Fariborz
• Application Number:
  US13/372,498
• Publication Number:
  US 20120143846A1
• Time in Patent Office: 595 Days
• Field of Search: 707/713, 707/715
• US Class Current: 707/715
• CPC Class Codes: G06F 16/2445 Data retrieval commands; View definitions

Abstract

Disclosed are an apparatus, method, and program product which each provide an enhanced database engine. Access to precise values is provided while permitting unfettered access to those who are not interested in precise values. This is accomplished via an enhanced database index and indexing method. The entries of the database index are normalized to exclude precision. Individuals interested in precision can then specify precision as part of their query through use of a PRECISE keyword. Results are then filtered to account for the specified precision.

Claims

1. An apparatus, said apparatus comprising:

a processor;

memory;

an enhanced database index stored in said memory, said enhanced database index having normalized key values stored therein, said normalized key values representing non-normalized values; and

a program stored in said memory for accessing said enhanced database index, said program configured to select said normalized key values as return results and configured to select said non-normalized values as return results.

2. The apparatus of claim 1 wherein said program product is configured to select return results based upon a query language keyword.

3. The apparatus of claim 2 wherein the query language is structured query language (SQL).

4. The apparatus of claim 3 wherein said keyword is a PRECISE keyword which is added to the grammar of SQL.

5. A program product, said program product comprising:

non-transitory computer-readable media;

an enhanced database index stored on said non-transitory computer-readable media, said enhanced database index having normalized key values stored therein, said normalized key values representing non-normalized values; and

a program stored on said non-transitory computer-readable media for accessing said enhanced database index, said program configured to select said normalized key values as return results and configured to select said non-normalized values as return results.

6. The program product of claim 5 wherein said program product is configured to select return results based upon a query language keyword.

7. The program product of claim 6 wherein the query language is structured query language (SQL).

8. The program product of claim 7 wherein said keyword is a PRECISE keyword which is added to the grammar of SQL.

9. A program product, said program product comprising:

non-transitory computer-readable media;

a first program function stored on said non-transitory computer-readable media which maintains a database table having a plurality of entries and a plurality of columns, wherein a first column of said table contains entries in a numerical format supporting different precision, a first plurality of said entries containing respective values in said first column represented in a first precision, and a second plurality of said entries containing respective values in said first column represented in a second precision different from said first precision;

a second program function which maintains an index for said database table, said index containing normalized values representing said values in said first column, said normalized values being represented in a common precision;

a third program function which, responsive to database queries of a first type, identifies values in said first column which have different precision but identical normalized representation in said index as equivalent; and

a fourth program function which, responsive to database queries of a second type, identifies values in said first column which have different precision but identical normalized representation in said index as not equivalent.

10. The program product of claim 9 wherein said numerical format is a decimal floating point format.

11. The program product of claim 9 wherein each said database query contains a query language keyword determining whether the query is a query of said first type or a query of said second type.