Enhanced Path-Based Row Source for XML Aggregation

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Querying binary-encoded XML data in object-relational databases is inefficient due to the need for additional computation to decode and interpret the data, which slows down processing and manipulation.

Innovation Solution

Implementing an enhanced path-based row source that computes aggregation functions directly within the database server, eliminating the need for intermediate XPath evaluation results and optimizing query execution plans to improve performance.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If binary-encoded XML data is stored in object-relational databases, then storage efficiency and network bandwidth are improved, but query processing time increases due to additional decoding computation

Engineering Contradiction:

Improvestorage efficiencyVSAvoidquery processing time

Core Design Contradiction:

Quantity of substanceVSLoss of time

Solution Approach 1:

The patent pre-computes and stores aggregation results (such as COUNT, SUM, MIN, MAX) in the binary-encoded XML structure itself, so that when queries are executed, the database server can directly retrieve these pre-computed values without performing additional decoding and aggregation operations, thus resolving the time penalty of binary encoding

Inventive Principle:

Principle #10Preliminary action

2Reliability

If intermediate XPath evaluation results are generated during query processing, then query flexibility and correctness are maintained, but processing overhead and memory usage increase

Engineering Contradiction:

Improvequery correctnessVSAvoidprocessing overhead

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent extracts and eliminates the need for intermediate XPath evaluation results by directly evaluating aggregation functions on the binary-encoded XML data using optimized algorithms that work natively with the binary format, thus removing the unnecessary intermediate step while maintaining query correctness

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent creates a universal query processing mechanism that can handle both simple retrieval and aggregation functions directly on binary-encoded XML data without requiring conversion to intermediate XPath representations, making the system more efficient across multiple query types

Inventive Principle:

Principle #6Universality (Multi-functionality)

Data Source

PatentUS8301620B2Efficient way to evaluate aggregations on XML data using path-based row sources

Publication Date: 2012.10.30 ORACLE INT CORP

AI summary

The approaches described herein provide an efficient way for a database server to process certain kinds of queries that require the evaluation of an aggregation function over XML data stored in an object-relational database. An aggregation function takes multiple inputs and generates a single output. A database server first determines whether the query qualifies for this particular kind of optimization, then creates a query execution plan that specifies the use of an enhanced path-based row source, eliminating the need for a second path-based row source for computing the aggregation function. The enhanced path-based row source specified in the query execution plan computes an aggregation function and stores the result of that function computation in a column of each row. The XPath evaluation results that are the individual inputs to the aggregation function are only stored temporarily until they are used to compute the aggregation function.