Databases Reference
In-Depth Information
which, in Chapter 12, we showed how to
internalize
within the production
tables which are their destinations or points of origin. (From Chapter 13.)
retroactive delete
Mechanics:
a temporal delete transaction that specifies an effective begin date
that is earlier than Now().
Semantics:
a temporal delete transaction that removes the representation of an
object from one or more clock ticks in past effective time.
Comments:
In a conventional table, the only mistake in data that can be corrected is a
mistake in data values, and the correction is done “destructively”, by
overwriting the old data.
But in an asserted version table, there are two other mistakes in data. One is to
mistakenly claim that an object was represented during a past effective time
period. The other is to mistakenly claim that an object was not represented
during a past effective time period. A retroactive delete transaction is the
means by which the former mistake is corrected. A retroactive insert
transaction is the means by which the latter mistake is corrected.
Components:
clock tick, effective begin date, Now(), object, represent, past
version, temporal transaction.
retroactive insert
Mechanics:
a temporal insert transaction that specifies an effective begin date
that is earlier than Now().
Semantics:
a temporal insert transaction that adds the representation of an object
to one or more clock ticks in past effective time.
Comments:
See also:
retroactive delete
.
Components:
clock tick, effective begin date, Now(), object, represent, past
version, temporal transaction.
retroactive transaction
Mechanics:
a temporal transaction that specifies an effective begin date that is
earlier than Now().
Semantics:
a temporal transaction which alters the effective-time past.
Comments:
See also:
proactive transaction
.
Components:
temporal transaction, effective begin date.
retroactive update
Mechanics:
a temporal update transaction that specifies an effective begin date
that is earlier than Now().
Semantics:
a temporal update transaction that changes the business data
representing an object in one or more clock ticks in past effective time.
Components:
business data, clock tick, effective time, object, represent, temporal
transaction.
retrograde movement
Mechanics:
changing the assertion begin date on a deferred assertion to an earlier
date.
Semantics:
the movement of a deferred assertion from far future to near future
assertion time.
Components:
assertion begin date, deferred assertion, far future assertion time,
near future assertion time.
