> Bottom line - how stable are any of those databases after making the
> sort of complex metadata changes that are possible in Firebird?

I'm not making a complex metadata change, I merely automatically
creating the initial structure automatically. Which is a very common
approach, usability-wise.

> Oracle is probably the only one that could be relied on, but even there
> they realise that the 'professional' way of making major updates is NOT
> to do it on live data - but you need extra oracle staff to manage that
> :)
>
> Personally I have come across several examples of changing or applying
> constraints that failed because of 'unexpected' data in the database.
> Even after you can prove that a change will not cause problems - sods
> law says it will ;)

There is no data. The structure is being populated from scratch. There
are no other connections in use by other users. The whole structure is
created in one go and will only be changed in one go again when an
upgrade occurs. Then the same previous testing structure
creation/modification will be applied in one go during an upgrade
wizard.

I can understand that you prevent this change when actual statements
are still open for it, just like you do with drop table. I don't
understand why you artificially seem to enforce total isolation just
for the creation of foreign keys.

--
Geert Bevin Uwyn bvba
"Use what you need" Avenue de Scailmont 34
http://www.uwyn.com 7170 Manage
gbevin[remove] at uwyn dot com Tel +32 64 84 80 03

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