Mengmeng Chen

US Patent:

8572051, Oct 29, 2013

Filed:

Aug 8, 2012

Appl. No.:

13/569377

Inventors:

Mengmeng Chen - Belmont CA, US
Yali Zhu - Foster City CA, US
Thierry Cruanes - Foster City CA, US
Alan Wood - San Jose CA, US

Assignee:

Oracle International Corporation - Redwood Shores CA

International Classification:

G06F 17/30

US Classification:

707687, 7079992

Abstract:

Parallel execution of SQL statements is made fault-tolerant. Specifically, during parallel query processing, a new row source is created that allows checkpoints to be stored at certain points in the query processing. If a failure occurs, then the query can be restarted from the most recent checkpoint (rather than from the very beginning of the query). The checkpoints are implemented at operation boundaries where rows need to be redistributed among processes. These are natural checkpoint locations because (1) each subsequent operation can proceed from the output of the previous operation, which is stored as a checkpoint, and (2) these operation completions tend to be points in the computation where the query state is minimized, thus minimizing checkpoint storage requirements.

US Patent:

20150269202, Sep 24, 2015

Filed:

Mar 19, 2015

Appl. No.:

14/663210

Inventors:

- Plano TX, US
Ron-Chung Hu - Palo Alto CA, US
Mengmeng Chen - San Jose CA, US

International Classification:

G06F 17/30

Abstract:

A method of dynamically computing an optimal materialization schedule for each column in a column oriented RDBMS. Dynamic column-specific materialization scheduling in a distributed column oriented RDBMS is optimized by choosing a materialization strategy based on execution cost including central processing unit (CPU), disk, and network costs for each individual exchange operator. The dynamic programming approach is computationally feasible because the optimal schedule for a sub-plan is path independent.