Re: Remove obsolete information schema tables

On 2019-10-21 07:34, Michael Paquier wrote:
> On Sun, Oct 20, 2019 at 10:01:09AM +0200, Peter Eisentraut wrote:
>> On 2019-10-17 09:44, Michael Paquier wrote:
>>> I have a question here. Per the notes in information_schema.sql,
>>> SQL_SIZING_PROFILES has been removed in SQL:2011,
>>
>> OK, we can remove that one as well. New patch attached.
>
> Looks fine.

committed

>>> attributes.isnullable and DOMAIN_UDT_USAGE in SQL:2003~. Would it
>>> make sense to cleanup those ones?
>>
>> OK, I'll look into those, but it seems like a separate undertaking. We
>> don't always remove things just because they were dropped by the SQL
>> standard.
>
> But that's the same kind of cleanup you do here. What's the
> difference with DOMAIN_UDT_USAGE, which is mentioned as removed from
> SQL:2003?

SQL_LANGUAGES for example, contains information about which version of
the SQL standard is being conformed to. But since it's no longer in the
standard, it most recently said that SQL:2003 is supported, which isn't
very useful. We could extrapolate new values for more recent standards,
but that's also questionable. So it makes sense to remove it.

By contrast, I don't know why DOMAIN_UDT_USAGE was removed. It might
still be useful. Just because something is dropped by an SQL standard,
it doesn't mean we should remove it. For example, bit and bit varying
are no longer in the standard.

--
Peter Eisentraut http://www.2ndQuadrant.com/
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