ODM - Observations Data Model

The latest release CUAHSI Observations Data Model, is described on the CUAHSI HIS Web site at: http://his.cuahsi.org/odmdatabases.html

Use cases illustrating how data types fit into ODM are described at

Items for Consideration for future ODM releases

  • Include time step spacing as an item in the series catalog
  • Add variableCode or CategoryCode to Categories table. CategoryCode to provide a short identifier for categories. Variablecode to facilitate identification of associated variables.
  • Add a SiteType field in the Sites table and a SiteTypeCV table that describes the different types of SiteTypes.
  • Add indexes to enhance efficiency.
  • Address the concepts of networks within ODM, to for example identify Panola, Corpus Christi separately when they are in the same database.
  • Add a replicate number to the Values table to deal with replicate samples.
  • EndDataValue in SeriesCatalog. This would be used to for example plot a map of the most recent value as in Waterwatch.
  • Add Ability to show the best dataseries for a variable, at a location. Need to be able to flag a series as the one to display/use.
  • Address the capability to have multiple qualifiers associated with a single observation (modification of qualifiers table). This could be implemented using a join table, but would inhibit the interpretability of qualifiers.
    A possible implementation for multiple qualifiers is exactly analagous to DerivedFrom. The field QualifierId in DataValues is replaced by QualifierSetId. A new table QualifierSets has two fields, QualifierSetId {FK} and QualifierId {FK}. The QualifierSetId is repeated for every qualifier associated with a DataValue. The field QualifierID points to the Qualifiers table.
  • Revisit the mandatory (i.e. Nulls not allowed) constraint on the Variables.NoDataValue field.
  • Define levels in ODM. e.g. ODM lite to be ODM with only the mandatory variables. ODM core to be ODM as it is presently implemented with many fields optional. Develop guidelines for extending ODM beyond core. ODM for catalogs to be ODM core without the DataValues table.
  • Add an Events join table and an EventDescriptions table to enable the storage of sampling events.
  • Link data series to values using a join table
  • Handle SI conversion in Units
  • Groups of Groups. Groups of Sites. Groups of sites can be conceptualized as a geometric feature: i.e. measurements on a curve, transect, within a watershed, etc.
  • Ownership, security, authentication, auditing
  • Address the question of "locations" that may have multiple sites, for example their may be EPA and USGS data collected at the same location but that are reflected as different sites in ODM because of different sitecodes. One way to address this would be through the use of sitegroups similar to observation groups in ODM.
  • A vocabulary field in sources to support of multiple vocabularies, and semantic translations.