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8. Details of Individual Metadata Elements

8.31 Identifier




Identifying Attributes





Defined by

Dublin Core Metadata Element Set, v1.1

Element URI

Definitional Attributes

DC Definition

An unambiguous reference to the resource within a given context.

DC Comment

Recommended best practice is to identify the resource by means of a string or number conforming to a formal identification system. Example formal identification systems include the Uniform Resource Identifier (URI) (including the Uniform Resource Locator (URL), the Digital Object Identifier (DOI) and the International Standard Book Number (ISBN).


To uniquely identify the record.

To distinguish one record from another.

To facilitate retrieval.

To avoid duplication of records.


"Registration specifies the following metadata as a minimum: a) a unique identifier assigned from the system..." ISO Technical Report 15489-2, s. 4.3.3

"A useable record is one that can be located, retrieved, presented and interpreted." ISO International Standard 15489-1, s. 7.2.5

"The movement of records should be documented to ensure that items can always be located when required. Tracking mechanisms may record the item identifierů" ISO International Standard 15489-1, s. 9.8.3

"The primary purpose of registration is to provide evidence that a record has been created or captured in a records system, and an additional benefit is that it facilitates retrieval. It involves recording brief descriptive information or metadata about the record and assigning the record an identifier, unique within the system." ISO International Standard 15489-1, s. 9.4

"Metadata should be used to identify records and facilitate their retrievability and usability in records systems. A records system should provide ready access to all relevant records and their related metadata." ISO Technical Specification 23081-1, s. 9.2.3

Value Domain

Unique non-enumerated strings.

Datatype Name



Applicable at record level; applicable at file level.


Mandatory at record level; mandatory at file level.

Relational Attributes

Encoding Scheme






Conditions of Application - Record


Free text


Pre Record Declared Locked

Post Record Declared Locked




Not repeatable

Conditions of Application - File


Free text




Not repeatable

Comments and Guidance

a) Explanation of Definition/Usage

The Identifier is a system-generated numeric code that unambiguously identifies a record or file upon creation. The Identifier provides the link between the actual record and the metadata attached to it.

This code is not to be confused with an entry from a classification scheme / file plan.

b) Best Practices

The value for this element should be a numeric code that is system generated. As each record is entered into the EDRMS, it is given the next number in the sequence.

The value for this element may not be modified as once it is applied, it stays with the record or file throughout its life cycle.

c) Obligation

This element is mandatory to unambiguously distinguish one record from another and one file from another.

d) Default Values/Auto-populate

This is a system-generated value inherent to most EDRMS and is therefore auto-populated.

e) Linkages


f) Examples

  1. "139072"

  2. "783905"

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