Method and apparatus for estimating the number of distinct values in a database
CA 2242001 A1 · Owner: Informix Software, Inc. · Inventors: Yan, Weipeng
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method and apparatus for estimating the number of distinct values in a database table selects one of several numerical methods to solve a model of the number of distinct values in a database table based on a table size, a sample size, and the number of distinct values in the sample. The sample may be a sample previously collected for purposes other than to estimate the number of distinct values, and the number of records in the sample and the number of distinct values in the sample may be determined at the time the sample was collected.
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed June 29, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended June 29, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 29, 2020.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.