System and method for processing and decomposition of a multidimensional query against a relational data source

• US 20060294087A1
• Filed: 06/23/2005
• Published: 12/28/2006
• Est. Priority Date: 06/23/2005
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Mordvinov, Vladimir
• Granted Patent: US 8,935,273 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 16/24528 Standardisation; Simplification
• CPC Class Codes: G06F 16/283 Multi-dimensional databases or data warehouses, e.g. MOLAP or ROLAP

Abstract

A multidimensional operation provider is provided for processing a multidimensional query against a relational datasource. The multidimensional operation provider comprises a query interceptor, a query decomposer and a query replacer. The query interceptor detects and intercepts a multidimensional query that is issued against one or more relational data sources. The query decomposer decomposes expressions of the multidimensional query into one multidimensional expression and/or one or more relational expressions. The query replacer replaces the multidimensional query with a stack of operations expressed by the decomposed multidimensional expressions and/or the relational expressions.

Claims

1. A multidimensional operation provider for processing a multidimensional query, the multidimensional operation provider comprising:

a query interceptor for detecting and intercepting a multidimensional query that is issued against one or more relational data sources;

a query decomposer for decomposing expressions in the multidimensional query into one or more multidimensional expressions and/or one or more relational expressions; and

a query replacer for replacing the multidimensional query with a stack of operations expressed by the decomposed multidimensional expressions and/or the relational expressions.

2. The multidimensional operation provider as recited in claim 1, wherein the query replacer allows operations expressed by the decomposed multidimensional expressions to be sent to an Online Analytical Processing (OLAP) query provider that is capable of executing multidimensional query operations, and operations expressed by the decomposed relational expressions to be sent to a relational query provider that is capable of executing relational query operations.

3. The multidimensional operation provider as recited in claim 1, wherein the query decomposer comprises

a sub-expression identifier for identifying if one or more parts of expressions in the multidimensional query that are supported by a relational query provider that is capable of executing relational query operations, and for creating a tabular operation sub-query based on the parts of expressions that meet the criteria of a tabular data item.

4. The multidimensional operation provider as recited in claim 3, wherein the query decomposer further comprises:

a tabular expression extractor for extracting one or more tabular sub-expressions in the multidimensional query into tabular data items;

a cube item creator for creating a cube item in a dynamic cube for each tabular data item; and

an expression replacer for replacing the tabular sub-expressions with references to their corresponding cube items.

5. The multidimensional operation provider as recited in claim 4, wherein the cube item creator uses a dynamic cube cacher that allows caching of the dynamic cube.

6. The multidimensional operation provider as recited in claim 1, wherein the query decomposer further comprises a name decoration operator for performing member unique name decoration operations.

7. The multidimensional operation provider as recited in claim 3 wherein the query decomposer uses an operation support table describing operations supported by the tabular operation sub-query.

8. A query decomposer for decomposing multidimensional queries, the query decomposer comprising:

a sub-expression identifier for identifying if one or more parts of expressions in a multidimensional query that meet tabular data item criteria, and

a tabular operation sub-query creator for creating a tabular operation sub-query based on the parts of expressions that are supported by the relational query provider and meet tabular data item criteria.

9. The query decomposer as recited in claim 8, wherein the sub-expression identifier identifies one or more parts of expressions as tabular sub-expressions that meet tabular data item criteria;

and the query decomposer further comprises;

a tabular expression extractor for extracting the identified tabular sub-expressions into tabular data items;

a cube item creator for creating a cube item in a dynamic cube for each tabular data item; and

.

an expression replacer for replacing the identified tabular sub-expressions in the multidimensional query with references to their corresponding cube items.

10. The query decomposer as recited in claim 9 wherein the cube item creator uses a dynamic cube cacher that allows caching of the dynamic cube.

11. The query decomposer as recited in claim 9 wherein the query decomposer uses an operation support table describing operations supported by the tabular operation sub-query.

12. The query decomposer as claimed in claim 9 further comprises a name decoration operator for performing member unique name decoration operations.

13. A method of processing a multidimensional query against one or more data source, the method comprising steps of:

detecting and intercepting a multidimensional query that is issued against one or more relational data sources;

decomposing expressions of the multidimensional query into one or more multidimensional expressions and/or one or more relational expressions; and

replacing the multidimensional query with a stack of operations expressed by the decomposed multidimensional expressions and/or the relational expressions for execution of the operations.

14. The method as recited in claim 13, wherein the replacing step allows operations expressed by the decomposed multidimensional expressions to be sent to an Online Analytical Processing (OLAP) query provider that is capable of executing multidimensional query operations, and operations expressed by the decomposed relational expressions to be sent to a relational query provider that is capable of executing relational query operations.

15. The method as recited in claim 14, wherein the decomposing step comprises the steps of:

identifying if one or more parts of expressions in the query that are supported by a relational query provider that is capable of executing relational queries, and for creating a tabular operation sub-query based on the parts of expressions that are supported by the relational query provider.

16. The method as recited in claim 15, wherein the decomposing step further comprises the steps of:

extracting one or more tabular sub-expressions in the multidimensional query into tabular data items;

creating a cube item in a dynamic cube for each tabular data item; and

replacing the tabular sub-expressions with references to their corresponding cube items.

17. The method as recited in claim 16 further comprising the step of allowing caching of the dynamic cube.

18. The method as recited in claim 13, wherein the decomposing step further comprises the step of performing member unique name decoration operations.

19. The method as recited in claim 13 wherein the decomposing step uses an operation support table describing operations supported by tabular operation sub-query.

20. A method of decomposing a multidimensional query applied against one or more relational data sources, the method comprising the steps of:

identifying one or more parts of expressions as tabular sub-expressions that are supported by a relational query provider that is capable of executing relational queries;

extracting the identified tabular sub-expressions into tabular data items;

creating a cube item in a dynamic cube for each tabular data item; and

replacing the identified tabular sub-expressions in the multidimensional query with references to their corresponding cube items.

21. The method as recited in claim 20, wherein the identifying step uses tabular data item criteria including the operations that are pushable to a tabular data item.

22. The method as recited in claim 20, wherein the extracting step performs data item aggregation.

23. The method as recited in claim 20, wherein the cube item creating step determines a role of the created cube item in accordance with predetermined cube construction rules.

24. The method as recited in claim 20, wherein the replacing step creates an Online Analytical Processing (OLAP) operation sub-query that is executable by an OLAP query driver.

25. The method as recited in claim 20 further comprising the step of performing member unique name decoration operations.

26. A memory containing computer executable instructions that can be read and executed by a computer for caring out a method of processing a multidimensional query against one or more data source, the method comprising the steps of:

detecting and intercepting a multidimensional query that is issued against one or more relational data sources;

decomposing expressions of the multidimensional query into one or more multidimensional expressions and/or one or more relational expressions; and

replacing the multidimensional query with a stack of operations expressed by the decomposed multidimensional expressions and/or the relational expressions for execution of the operations.

27. A carrier carrying a propagated signal containing computer executable instructions that can be read and executed by a computer, the computer executable instructions being used to execute a method of processing a multidimensional query against one or more data source, the method comprising the steps of:

detecting and intercepting a multidimensional query that is issued against one or more relational data sources;

decomposing expressions of the multidimensional query into one or more multidimensional expressions and/or one or more relational expressions; and

replacing the multidimensional query with a stack of operations expressed by the decomposed multidimensional expressions and/or the relational expressions for execution of the operations.