Lesson plan
HHCode
A Helical Hyperspatial Code, also known as an HHCode, is a data storage format for very large spatio-temporal datasets. The development of HHCode can be traced to efforts in the 1990's by Edric Keighan, Panagiotis A. Vretanos, Michael Galluchon, and Herman P. Varma while working for the Canadian Hydrographic Service's Atlantic regional offices at the Bedford Institute of Oceanography in Dartmouth, Nova Scotia. CHS was facing a problem with storing very large spatial datasets acquired during hydrographic surveys (thus having a temporal element) and was seeking a method to store the datasets in a relational database structure. CHS scientists reportedly conceptualized a spatio-temporal indexing system during a hydrographic survey onboard CCGS Hudson on Georges Bank during the summer of 1989. The indexing system involved an adaptation of a Riemannian hypercube data structure, invoking a helical spiral through 3-dimensional space, which allowed for n-size of features. The actual implementation of the proposed indexing system was termed a helical hyperspatial code and it was first used by modifying an installation of the Oracle database version 4. The HHCode indexing system permitted a highly efficient compression of not only spatial data but other data types as well, while improving search and retrieval times.…
Article summary
A Helical Hyperspatial Code, also known as an HHCode, is a data storage format for very large spatio-temporal datasets. The development of HHCode can be traced to efforts in the 1990's by Edric Keighan, Panagiotis A. Vretanos, Michael Galluchon, and Herman P. Varma while working for the Canadian Hydrographic Service's Atlantic regional offices at the Bedford Institute of Oceanography in Dartmouth, Nova Scotia. CHS was facing a problem with storing very large spatial datasets acquired during hydrographic surveys (thus having a temporal element) and was seeking a method to store the datasets in a relational database structure. CHS scientists reportedly conceptualized a spatio-temporal indexing system during a hydrographic survey onboard CCGS Hudson on Georges Bank during the summer of 1989. The indexing system involved an adaptation of a Riemannian hypercube data structure, invoking a helical spiral through 3-dimensional space, which allowed for n-size of features. The actual implementation of the proposed indexing system was termed a helical hyperspatial code and it was first used by modifying an installation of the Oracle database version 4. The HHCode indexing system permitted a highly efficient compression of not only spatial data but other data types as well, while improving search and retrieval times.…
Key claims
No claims recorded.
Discussion questions
- Summarise the article in your own words. Which single claim would you verify first, and why?
- Which claim in this article is most likely to be revised as the sources update? How would you check its current status?
- If two sources disagreed about one of these facts, what would you need in order to trust one over the other?
Bibliography
No sources recorded.
Key claims and bibliography are generated from the same tracked claims and sources as the article page.