Kbase P13680: How to undo changes to database structure.
| Autor |
Progress Software Corporation - Progress |
| Acesso |
Público |
| Publicação |
18/03/2003 |
|
Status: Unverified
GOAL:
How to undo changes to database structure.
GOAL:
Can Progress create a "rollback" or "reverse" df?
FIX:
Customers sometimes ask if Progress has anything like a "rollback" or "reverse" df for undoing changes that a delta.df has made to a database.
In order to undo such changes, create a delta.df again and apply it to change back the structure. You would need to have a copy of the previous structure available in order to do this, and it would be compared with the existing (changed) structure.
The changes can also be rolled back manually from the Data Dictionary, or from a 4GL procedure.
Records that have been added after the changes to the database have been made will be affected in that when the changes are "rolled back", the records will lose the fields or tables that were added previously.
If data had already been entered into e.g. a new table and this new table is then later to be removed, then the data would need to be dumped out from that table before it is deleted if you still want that data to be available at some point in the future.