Yiu L Lau

US Patent:

20180144029, May 24, 2018

Filed:

Sep 26, 2017

Appl. No.:

15/716345

Inventors:

- Redwood Shores CA, US
Junyi Xie - Dobbs Ferry NY, US
Yiu Woon Lau - New York NY, US

International Classification:

G06F 17/30

Abstract:

Techniques are provided for sharing expression evaluation across a database management system and a storage layer. In an embodiment, a computer identifies, in a query execution plan compiled for a query, a plurality of target operators that includes an expression that computes a common value. A storage layer evaluates the expression that computes the common value during a table scan of stored data indicated by the expression. For at least one target operator of the plurality of target operators, the computer modifies a row input of the at least one target operator to add a column to receive an evaluation result comprising the common value from the storage layer. The query execution plan is performed by a database management system and the storage layer.

US Patent:

20140258266, Sep 11, 2014

Filed:

Mar 6, 2013

Appl. No.:

13/787663

Inventors:

- Redwood Shores CA, US
Junyi Xie - Dobbs Ferry NY, US
Yiu Woon Lau - New York NY, US

International Classification:

G06F 17/30

US Classification:

707718

Abstract:

Techniques are provided for sharing expression evaluation across a database management system and a storage layer. According to an embodiment, a plurality of target operators are identified that include a common expression. Each respective target operator corresponds to a step that evaluates the common expression during query execution. The plurality of target operators are modified to enable sharing of an evaluation result of the common expression. The query is executed according to the target operators. During query execution, the evaluation result is shared by the target operators. In other embodiments, the evaluation of the common expression is pushed to a storage layer. During query execution, a database management system retrieves the evaluation result of the common expression from the storage layer.