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documentation:cdm:concept_relationship

CONCEPT_RELATIONSHIP table

The CDM documentation is now being housed on github. The most recent release is v5.2

The CONCEPT_RELATIONSHIP table contains records that define direct relationships between any two Concepts and the nature or type of the relationship. Each type of a relationship is defined in the RELATIONSHIP table.

FieldRequiredTypeDescription
concept_id_1YesintegerA foreign key to a Concept in the CONCEPT table associated with the relationship. Relationships are directional, and this field represents the source concept designation.
concept_id_2YesintegerA foreign key to a Concept in the CONCEPT table associated with the relationship. Relationships are directional, and this field represents the destination concept designation.
relationship_idYesvarchar(20)A unique identifier to the type or nature of the Relationship as defined in the RELATIONSHIP table.
valid_start_dateYesdateThe date when the instance of the Concept Relationship is first recorded.
valid_end_dateYesdateThe date when the Concept Relationship became invalid because it was deleted or superseded (updated) by a new relationship. Default value is 31-Dec-2099.
invalid_reasonNovarchar(1)Reason the relationship was invalidated. Possible values are 'D' (deleted), 'U' (replaced with an update) or NULL when valid_end_date has the default value.

Conventions

  • Relationships can generally be classified as hierarchical (parent-child) or non-hierarchical (lateral).
  • All Relationships are directional, and each Concept Relationship is represented twice symmetrically within the CONCEPT_RELATIONSHIP table. For example, the two SNOMED concepts of ‘Acute myocardial infarction of the anterior wall’ and ‘Acute myocardial infarction’ have two Concept Relationships: 1- ‘Acute myocardial infarction of the anterior wall’ ‘Is a’ ‘Acute myocardial infarction’, and 2- ‘Acute myocardial infarction’ ‘Subsumes’ ‘Acute myocardial infarction of the anterior wall’.
  • There is one record for each Concept Relationship connecting the same Concepts with the same relationship_id.
  • Since all Concept Relationships exist with their mirror image (concept_id_1 and concept_id_2 swapped, and the relationship_id replaced by the reverse_relationship_id from the RELATIONSHIP table), it is not necessary to query for the existence of a relationship both in the concept_id_1 and concept_id_2 fields.
  • Concept Relationships define direct relationships between Concepts. Indirect relationships through 3rd Concepts are not captured in this table. However, the CONCEPT_ANCESTOR table does this for hierachical relationships over several “generations” of direct relationships.
  • In previous versions of the CDM, the relationship_id used to be a numerical identifier. See the RELATIONSHIP table.
documentation/cdm/concept_relationship.txt · Last modified: 2017/08/17 15:19 by clairblacketer