Invention Grant
- Patent Title: Reclustering of database tables based on peaks and widths
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Application No.: US16941215Application Date: 2020-07-28
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Publication No.: US10956394B2Publication Date: 2021-03-23
- Inventor: Jiaqi Yan , Thierry Cruanes , Jeffrey Rosen , William Waddington , Prasanna Rajaperumal , Abdul Munir
- Applicant: Snowflake Inc.
- Applicant Address: US CA San Mateo
- Assignee: Snowflake Inc.
- Current Assignee: Snowflake Inc.
- Current Assignee Address: US CA San Mateo
- Agency: Schwegman Lundberg & Woessner, P.A.
- Main IPC: G06F16/22
- IPC: G06F16/22 ; G06F16/28 ; G06F7/08 ; G06F16/27

Abstract:
The subject technology determines whether a table is sufficiently clustered. The subject technology in response to determining the table is not sufficiently clustered, selects one or more micro-partitions of the table to be reclustered. The subject technology constructs a data structure for the table. The subject technology extracts minimum and maximum endpoints for each micro-partition in the data structure. The subject technology sorts each of one or more peaks in the data structure based on height. The subject technology sorts overlapping micro-partitions based on width. The subject technology selects based on which micro-partitions are within the tallest peaks of the one or more peaks and further based on which of the overlapping micro-partitions have the widest widths.
Information query