--- In firebird-support@yahoogroups.com, Carsten Schäfer
<ca_schaefer@...> wrote:

>
> Of course not.
> Btw even if someone would remove the primary key and then insert a
> duplicate value wouldn't it impossible to reinsert the primary key

again ?

>
> Carsten
>

It would be impossible to reinsert the primary key through DDL (ALTER
TABLE ADD CONSTRAINT ....), because (as you expect) it does checks the
value when activating.

What was suggested was that someone (or some tool) may have manually
modified the system tables without going through the official channel
of using DDL. (adding a record to RDB$RELATION_CONSTRAINTS for
example). As you know, modifying the system tables directly is a bad
idea full stop end of story.

I doubt this is the case here because you would not be asking us how it
happenned had you treated the database to that sort of abuse. I have
responded with my theories in another thread.

Adam