Efficient large-scale filtering and/or sorting for querying of column based data encoded structures
US8478775B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 30, 2009 |
| Grant date | Jul 2, 2013 |
| Priority date | — |
| Expiry date | Sep 13, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F16/24561
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
The subject disclosure relates to querying of column based data encoded structures enabling efficient query processing over large scale data storage, and more specifically with respect to complex queries implicating filter and/or sort operations for data over a defined window. In this regard, in various embodiments, a method is provided that avoids scenarios involving expensive sorting of a high percentage of, or all, rows, either by not sorting any rows at all, or by sorting only a very small number of rows consistent with or smaller than a number of rows associated with the size of the requested window over the data. In one embodiment, this is achieved by splitting an external query request into two different internal sub-requests, a first one that computes statistics about distribution of rows for any specified WHERE clauses and ORDER BY columns, and a second one that selects only the rows that match the window based on the statistics.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.