The effectiveTime
Specref |
---|
RefType | (field) |
---|
t | effectiveTime |
---|
|
and
fields in the
enable the use of a "log style" append-only data model to track all changes to each
, providing full traceability. Once released, a row in any of these files will always remain unchanged. Historic data is supplied in the
dating back to the first release in
format in 2002.
In order to change the properties of a current
(and, therefore, to create a new version of it), a new row is added to the applicable file, containing the updated fields, with the
field set to true and the timestamp in the
effectiveTime Specref |
---|
RefType | (field) |
---|
t | effectiveTime |
---|
|
field indicating the nominal date on which the new version was released.
To inactivate a
a new row is added, containing the same data as the final valid version of the
but with the
field set to false and the timestamp in the
effectiveTime Specref |
---|
RefType | (field) |
---|
t | effectiveTime |
---|
|
fi eld indicating the nominal date of the release in which the final version ceased being valid.
Where editorial policy does not allow a particular property of a
to be changed whilst keeping the same
the
as a whole is inactivated (as described above), and a new row added with a new id, the
effectiveTime Specref |
---|
RefType | (field) |
---|
t | effectiveTime |
---|
|
set to the nominal date of the release in which this version of the
became valid, and the
field set to true.
...
The following example demonstrates how the history mechanism works on the Concept file
, but the same rules apply equally well to the
and
member files. In this example, the
associated with the
moduleId and definitionStatusId and Specref |
---|
RefType | (field) |
---|
t | definitionStatusId |
---|
|
have been shown in place of their
SCTID values.
A new
(101291009) is ad ded on the 1st July 2007:
Id | effectiveTime | | moduleId | definitionStatusId (field) | t | definitionStatusId |
---|
|
|
---|
101291009 | 20070701 | 1 | | Concept |
---|
t | 900000000000074008|Primitive| |
---|
|
|
In the next release (on 1st January 2008), the
is moved from |Module 1| to |Module 2|. Because the moduleId field is not immutable, the
may be updated simply by adding a new record with the same Id.
Id | effectiveTime | | moduleId | definitionStatusId (field) | t | definitionStatusId |
---|
|
|
---|
101291009 | 20070701 | 1 | | Concept |
---|
t | 900000000000074008|Primitive| |
---|
|
|
101291009 | 20080101 | 1 | | Concept |
---|
t | 900000000000074008|Primitive| |
---|
|
|
In the next release (on 1st July 2008), the
is changed from being
to being
Id | effectiveTime | | moduleId | definitionStatusId (field) | t | definitionStatusId |
---|
|
|
---|
101291009 | 20070701 | 1 | | Concept |
---|
t | 900000000000074008|Primitive| |
---|
|
|
101291009 | 20080101 | 1 | | Concept |
---|
t | 900000000000074008|Primitive| |
---|
|
|
101291009 | 20080701 | 1 | | Concept |
---|
t | 900000000000073002|Defined| |
---|
|
|
In the next release (on 1st January 2009), the
is deactivated:
Id | effectiveTime | | moduleId | definitionStatusId (field) | t | definitionStatusId |
---|
|
|
---|
101291009 | 20070701 | 1 | | Concept |
---|
t | 900000000000074008|Primitive| |
---|
|
|
101291009 | 20080101 | 1 | | Concept |
---|
t | 900000000000074008|Primitive| |
---|
|
|
101291009 | 20080701 | 1 | | Concept |
---|
t | 900000000000073002|Defined| |
---|
|
|
101291009 | 20090101 | 0 | | Concept |
---|
t | 900000000000074008|Primitive| |
---|
|
|
...
At no stage in this process are previously written records ever amended. Once a record has been released in a
it will continue to be released in exactly the same form in future Changes are only recorded at the point of release in the
If a 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 not individual records showing each separate edit to the released In the last example, as well as inactivating the concept (active=0), the definitionStatusId
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 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| |
---|
|
.
...