Dropping columns from a table with minimized unavailability
US9910869B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 28, 2014 |
| Grant date | Mar 6, 2018 |
| Priority date | — |
| Expiry date | Oct 21, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F16/2282
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Dropping of columns from a table with data availability, where the columns in the table are each associated with a column number, includes: executing a statement to drop a given column in the table and deferring an application of the statement until a reorganization of a current data set including the table. When the reorganization of the current data set is performed, the reorganization includes: updating column numbers for columns in each row of the table using a mapping data structure to remove the given column; loading the plurality of data rows with the updated column numbers into a shadow data set; applying to the shadow data set any changes to the table that are concurrent with the reorganization; updating a schema definition of the table with the updated column numbers; and switching the current data set to the shadow data set.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.