Re: relation ### modified while in use

At 01:01 23/10/00 -0400, Tom Lane wrote:
>(It's barely possible that we could get away with allowing
>triggers to be added or deleted mid-transaction, but that doesn't feel
>right to me.)
>

A little OT, but the above is a useful feature for managing data; it's not
common, but the following sequence is essential to managing a database safely:

- Start TX
- Drop a few triggers, constraints etc
- Add/change data to fix erroneous/no longer accurate business rules
(audited, of course)
- Reapply the triggers, constraints
- Make sure it looks right
- Commit/Rollback based on the above check

It is very undesirable to drop the triggers/constraints in a separate
transaction since a communications failure could leave them unapplied. At
least in one TX, the recovery process should back out the TX.


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