OIMS OWL: data entities

We distinguish between data entity objects (DataEntityObject) and data entity concepts (DataEntityConcepts).

Data entity objects files, data sets and repositories that can be found through a URI. A Uniform Resource Identifier (URI) is a string of characters that unambiguously identifies a particular resource. To guarantee uniformity, all URIs follow a predefined set of syntax rules. The most common form of URI is the Uniform Resource Locator (URL), frequently referred to informally as a web address.

Data entity concepts are components of a human devised classification system that allows data resources to be grouped and combined in a meaningful way. Data entity concepts allow us to identify which data sets belong together in a single study. There is also a technical use for these concepts. They also allow us to link different data entity objects such as a data file and a metadata file. It therefore is imperative that we make it possible to link data entity objects to data entity concepts (isObjectOfConcept). A data entity object can belong to different data entity concepts if that is logical.

The data entity concept follows hierarchical principles. Hence different data entity concepts can have parent child relationships (isChildOf and isParentOf). The choice of parentage direction (being a child or a parent) depends on the nature of the data entity concepts and the linked data entity objects. Data entity concepts independent of their place in the hierarchy can have certain data entity objects attached to them we identify six types: (1) data entity metadata, (2) support documentation and information, (3) metadata-based ETL procedures and (4) the ETL procedure metadata, and (5) non-metadata based ETL procedures. For the metadata to count as such, it must be structured in a way that is described unambiguously as part of OIMS philosophy. Metadata that does not meet these requirements is considered support documentation, ETL procedures not described according to the OIMS philosophy are considered as non-metadata-based ETL procedures. Hence we have a number of ways to describe relationships.

A data entity object or a part of it can be the metadata file of a data entity concept (isMetadataObjectOfConcept) or a data entity object (isMetadataObjectOfObject). If a data entity object is part of a data entity concept then the metadata object related to the object is also part of the same data entity concept. A data entity object or a part of it can be the support documentation or information of a data entity concept (isSupportObjectOfConcept) or a data entity object (isSupportObjectOfObject). A metadata-based ETL procedure, even if it is quite generic is linked to one or more metadata file types (isEtlProcedureOfMetadataObjectType). This implies that data entity metadata objects have a typology (MetadataObjectType).