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Whenever you delete supertype
or subtype data, this affects the entire record constellation (the
supertype data and all corresponding subtype data).
When you delete supertype
data, all the associated subtype data is deleted as well.
Subtype data may be removed
from a record constellation by:
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Deleting a record in a window or info box based on the subtype
table (this causes the supertype data to be removed as well). |
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De-selecting the subtype indicator in a window or info box
based on the supertype table. |
As a result, the
corresponding subtype data is removed. If the subtype window is
open, its column displays become non-editable.
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Indirectly, by issuing an UPDATE <supertype> SET
<subtype indicator> = 'N' statement, or a DELETE FROM
<subtype> statement. Such a statement could be issued from a
constraint. |
What happens as a result of
removing subtype data depends on the value of the Delete Super on
Delete table attribute for the removed subtype.
If Delete Super on Delete is
set for that subtype, the supertype data and thereby the entire
record constellation is automatically removed. Fire On Delete
transition constraints on the record constellation are
evaluated.
If Delete Super on Delete is
not set for the removed subtype, the corresponding subtype
indicator in the supertype record is automatically de-selected.
This is handled as an UPDATE manipulation on the record
constellation. Fire On Update transition constraints defined on the
constellation are evaluated.
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