Techniques for updating join indexes
AssigneeTeradata US, Inc.
InventorsXiaobin Ma, Grace Kwan-On Au, Lu Ma
Life of this patent
Estimating the term…
Abstract
Techniques for updating join indexes are provided. A determination is made to update date criteria in a join index query statement. The join index is parsed for current date and current time criteria. The join index is revised based on the location of the current date and current time criteria as they appear in the original join index. The revisions include new criteria that minimize the effort in maintaining and using the join index.
Claims20
A method implemented and programmed within a non-transitory computer-readable storage medium and processed by a processor, the processor configured to execute the method, comprising:
- acquiring a query defining a join index;
- parsing the query to identify each occurrence and each context where a current date or current time condition is used;
- determining actions to take based on each occurrence and each context;
- and
- updating the query and the join index by using the actions to restate the query.
A method implemented and programmed within a non-transitory computer-readable storage medium and processed by a processor, the processor configured to execute the method, comprising:
- parsing a query that defines a join index;
- recording contexts for query statements within the query where a current date or current time condition is used;
- and
- evaluating each context and selectively modifying some or all of the query statements to rewrite the query.
A processor-implemented system, comprising:
- a processor configured with a join index updater, the join index updater residing in a non-transitory computer-readable medium and executes on the processor;
- the join index updater configured to parse a query that defines a join index and identify contexts and conditions used with current date or current time conditions within the query, the join index updater further configured to restate the query with modified statements to update the join index based on evaluation of the contexts and the conditions.
The system of dam 18, wherein the modified statements include ordered actions for a PARTITION BY clause between DELETE and INSERT actions of other clauses.
Dependencies are inferred from the claim text.