Limiting plan choice for database queries using plan constraints
US10268638B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 11, 2014 |
| Grant date | Apr 23, 2019 |
| Priority date | — |
| Expiry date | Jan 29, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG06F16/24544
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A database system allows users to specify plan constraint specification that limit choices of execution plans considered by an optimizer of the database system for optimizing database queries. The plan constraint specification specifies attributes of execution plans. The plan constraint specification may identify tables/intermediate results that the plan constraint is applicable to using table names or aliases. The database system applies the plan constraint specification to database queries that match the tables/aliases specified in the plan constraint specification. The database system limits the choice of execution plans evaluated for a database query to execution plans satisfying the attributes specified in an applicable plan constraint specification. The plan constraint specification may specify distribution of a table, a join order for tables, the join mechanism, cardinality of a table or intermediate result, and so on.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.