The

Specref
RefType (field) t effectiveTime

and

Gloss
PreSpace false t active

fields in the

Gloss
PreSpace false t release file

enable the use of a "log style" append-only data model to track all changes to each

Gloss
PreSpace false t component

, providing full traceability. Once released, a row in any of these files will always remain unchanged. Historic data is supplied in the

Gloss
PreSpace false t RF2

Gloss
PreSpace false t release files,

dating back to the first release in

Gloss
PreSpace false t RF1

format in 2002.

In order to change the properties of a current

Gloss
PreSpace false t component

 a new version of that component is created with the same identifier. This done by adding a new row to the relevant release file, with the column values updated to represent the changes. The

Gloss
PreSpace false t active

field must be set to true and the timestamp in the

Specref
RefType (field) t effectiveTime

field indicating the nominal date on which the new version was released. Note that the existing row is not changed in any way.

To inactivate a

Gloss
PreSpace false t component,

a new row is added, containing the same data as the final valid version of the

Gloss
PreSpace false t component,

but with the

Gloss
PreSpace false t active

field set to false and the timestamp in the

Specref
RefType (field) t effectiveTime

fi eld indicating the nominal date of the release in which the final version ceased being valid. Note again that the existing row is not changed in any way.

Where editorial policy does not allow a particular property of a

Gloss
PreSpace false t component

to be changed whilst keeping the same

Gloss
PreSpace false t Identifier,

the

Gloss
PreSpace false t component

as a whole is inactivated (as described above), and a new row added with a new id, the

Specref
RefType (field) t effectiveTime

set to the nominal date of the release in which this version of the

Gloss
PreSpace false t component

became valid, and the

Gloss
PreSpace false t active

field set to true.

It is thus possible to see both the current values and any historical values of a

Gloss
PreSpace false t component

at any point in time.

New content, changes and inactivations must have the

Specref
RefType (field) t effectiveTime

 for the release that it appears in. Pre-releases for testing may set the effectiveTime as the date of the future scheduled release but in general the effectiveTime must not be later that the scheduled release data,  Where there is a business requirement for specifying a future activation date for some

Gloss
PreSpace false t components,

this may be represented using

Gloss
PreSpace false t reference sets.

The following example demonstrates how the history mechanism works on the

Specref
RefType file t Concept

, but the same rules apply equally well to the

Gloss
PreSpace false t Description,

Gloss
PreSpace false t Relationship

and

Gloss
PreSpace false t Reference set

member files. In this example, the

Gloss
PreSpace false t descriptions

associated with the

Specref
RefType (field) t moduleId

and

Specref
RefType (field) t definitionStatusId

have been shown in place of their

Specref
RefType (data type) t SCTID

values.

A new

Gloss
PreSpace false t concept

 (101291009) is ad ded on the 1st July 2007:

Caption label
CapId -history-example-concept-added CapType Table
History Example - Concept Added

In the following release (on 1st January 2008), the

Gloss
PreSpace false t concept

is moved from |Module 1| to |Module 2|. Because the moduleId field is not immutable, the

Gloss
PreSpace false t concept

may be updated simply by adding a new record with the same Id.

Caption label
CapId history-example-module-change CapType Table
History Example - Module Change

In the following release (on 1st July 2008), the

Gloss
PreSpace false t concept

is changed from being

Gloss
PreSpace false t Primitive

to being

Gloss
PreSpace false t Fully defined.

Caption label
CapId history-example-definition-status-changed CapType Table
History Example - Definition Status Changed

In the following release (on 1st January 2009), the

Gloss
PreSpace false t concept

is deactivated:

Caption label
CapId history-example-concept-made-inactive- CapType Table
History Example - Concept Made Inactive

Notes

1. At no stage in this process are previously written records ever amended. Once a record has been released in a

   Gloss
   PreSpace false t release file,

   it will continue to be released in exactly the same form in future

   Gloss
   PreSpace false t release files.

2. Changes are only recorded at the point of release in the

   Gloss
   PreSpace false t RF2

   Gloss
   PreSpace false t release files.

   If a

   Gloss
   PreSpace false t component

   record is changed a number of times between releases (during an edit and review process), only the most recently amended record will be appended to the

   Gloss
   PreSpace false t release file,

   not individual records showing each separate edit to the released

   Gloss
   PreSpace false t component.

3. In the last example, as well as inactivating the concept (active=0), the

   Specref
   RefType (field) t definitionStatusId

   is changed from

   Concept
   t 900000000000073002|Defined| ShowFormat inline

    to

   Concept
   t 900000000000074008|Primitive|

   . In practice this change is not essential since the value of data columns is ignored when a

   Gloss
   PreSpace false t component

   is inactive. Although the change is unnecessary and insignificant, it typically occurs since all the relationships of an inactive concept must also be inactive, and as a result, from the perspective of the authoring environment the concept cannot be regarded as

   Concept
   t 900000000000073002|Defined|

   .

Related Links

• 3.1.4.1. Component features - History