Dependent vs. Independent Relationships

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Relationships between tables (or entities) in a database describe how records in one table reference or are linked to records in another. In Specify, these relationships are classified as either dependent or independent, which affects how data is handled during editing, especially in tools like Batch Edit or WorkBench.

You can see the types of relationships in the Data Model Viewer from the User Tools menu in any Specify 7 instance.

Dependent Relationship

A dependent relationship means that the existence of a record in the “child” table depends on the existence of a record in the “parent” table. If the parent is deleted, the dependent (child) should also be deleted. In editing scenarios, if all fields of a dependent record are cleared, the record can be safely deleted, since it cannot exist without its parent.

  • Example:
    • Collection Object → Determination
      • A Collection Object Determination cannot exist without a Collection Object.
      • If you delete a Collection Object, the dependent Determinations will also be deleted.
      • The Taxon records linked to the Determination will remain, as they are independent.

When using the WorkBench, you can upload new dependent records to existing records in the database (i.e. new Determinations, Preparations, etc.).

Independent Relationship

An independent relationship means that the related record can exist on its own, regardless of whether it is referenced by another record. The “child” is not owned by or tied to the “parent” in a way that its existence depends on it. In editing scenarios, clearing a reference to an independent record does not delete that record; it only removes the link.

  • Example:
    • Collection Object → Cataloger (Agent)
      • The Cataloger (an Agent) can exist independently of any Collection Object referencing it.
      • If you remove the Cataloger from a Collection Object, the Agent record is not deleted from the database.

You cannot update links to independent records using the WorkBench; instead, you must use the Batch Edit tool.

Examples of Dependent and Independent Relationships in Specify

Dependent Relationships

Parent Table Child/Related Table Direction Is the child record deleted if the parent is deleted? Can the child exist without the parent? Example Scenario
Collection Object Collection Object Attribute To-one dependent Yes No Deleting a Collection Object deletes its Collection Object Attribute.
Collection Object Determination To-many dependent Yes No Determinations are removed if the Collection Object is deleted.
Determination Determiner To-one dependent Yes No A Determiner record is deleted if its Determination is deleted.
Collecting Event Locality To-one dependent Yes No Locality is deleted if Collecting Event is deleted (when Locality is used as dependent).
Taxon Taxon Citation To-many dependent Yes No If a Taxon is deleted, its Taxon Citations are also deleted.
Agent Address To-many dependent Yes No Addresses linked as dependents to Agent are deleted if Agent is deleted.
Loan Loan Return To-many dependent Yes No Deleting a Loan deletes its associated Loan Returns.
Collection Object Preparation To-many dependent Yes No Preparations are deleted if their Collection Object is deleted.
Locality Geography To-one dependent Yes No Geography is deleted if its Locality is deleted (when used as dependent in schema).
Preparation Storage To-one dependent Yes No Storage is deleted if Preparation is deleted (if Storage is modeled as dependent).
Event Event Attribute To-many dependent Yes No All Event Attributes are deleted if the parent Event is deleted.
Collection Object Accession Object To-many dependent Yes No Accession Objects are deleted if the parent Collection Object is deleted.

Independent Relationships

Parent Table Child/Related Table Direction Is the child record deleted if the parent is deleted? Can the child exist without the parent? Example Scenario
Collection Object Cataloger (Agent) To-one independent No Yes Cataloger remains in database if Collection Object is deleted; only the link is removed.
Collection Object Collector (Agent) To-many independent No Yes Collector Agent records persist after Collection Object is deleted.
Collection Object Storage To-one independent No Yes Storage location exists independently of Collection Object references.
Determination Agent (Determiner) To-one independent No Yes Agent (Determiner) remains even if Determination is deleted.
Collection Object Collecting Event To-one independent No Yes Collecting Event is not deleted when a Collection Object is deleted.
Loan Borrower (Agent) To-one independent No Yes Agent (Borrower) is not deleted if Loan is deleted.
Locality Geography To-one independent No Yes Geography is not deleted if Locality is deleted (when Geography is independent in schema).
Collection Object Accession To-one independent No Yes Accession record remains after Collection Object is deleted.
Preparation Storage To-one independent No Yes Storage remains after Preparation is deleted (if Storage is independent in schema).
Collection Object Taxon (via Determination) To-one independent No Yes Taxon node remains in tree even if all Collection Objects referencing it are deleted.
Collection Object Preparation Type To-one independent No Yes Preparation Type persists after Collection Object is deleted.
Collection Object Collection To-one independent No Yes Collection record persists after all its Collection Objects are deleted.
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