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Database with native ISO datatypes

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Revision as of 18:56, 17 January 2009 by Yhavinga (talk | contribs)
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Summary

The ISO (or: Datatypes R2) data types can be implemented as 'native datatypes' at the database level. This may be an attractive option for RIMBAA applications.

Discussion

  • It would be great to have an Ad Hoc query and don't bother with the details of e.g. a PQ.
  • Grahame tried to implement UDT's in SQL-Server, but he did not like it because
    • no support for inheritence/substituability
    • the data is stored serialized as strings.
    • very difficult to address nested content (lists/sets)
  • Performance is an issue.
  • There might be a problem with current ORM implementations witch cannot currently handle UDT's.

PostgreSQL implementation

  • Yeb Havinga and Willem Dijkstra implemented UDT's in the PostgreSQL database management system, after a feasibility test with a few types in september '09 that turned out positive.
  • As yet we did not perform comparative tests, though we expect the PostgreSQL implementation to outperform implementations in the application layer.