ERD

erDiagram
  mkb_mapping_dmdpreparation {
    snomed_concept_id VARCHAR PK
    snomed_description_id VARCHAR FK
    drug_preparation_code_id VARCHAR FK
  }

  snomed_description {
    snomed_description_id VARCHAR PK
  }

  drug_code {
    emis_code_id VARCHAR PK
  }

  mkb_mapping_dmdpreparation }|--|{ snomed_description : "has_description"
  mkb_mapping_dmdpreparation }|--|{ drug_code : "maps_to_drug_code"