Postgres do not allow to create many tables with more than 63-symbols prefix

Moved from the pgsql-bugs mailing list [1].

On 6/23/22 07:03, Masahiko Sawada wrote:
> Hi,
>
> On Sat, Jun 4, 2022 at 4:03 AM Andrey Lepikhov
> <a(dot)lepikhov(at)postgrespro(dot)ru> wrote:
>>
>> According to subj you can try to create many tables (induced by the case
>> of partitioned table) with long prefix - see 6727v.sql for reproduction.
>> But now it's impossible because of logic of the makeUniqueTypeName()
>> routine.
>> You get the error:
>> ERROR: could not form array type name for type ...
>>
>> It is very corner case, of course. But solution is easy and short. So,
>> why not to fix? - See the patch in attachment.
>
> While this seems to be a good improvement, I think it's not a bug.
> Probably we cannot backpatch it as it will end up having type names
> defined by different naming rules. I'd suggest discussing it on
> -hackers.
Done.

> Regarding the patch, I think we can merge makeUniqueTypeName() to
> makeArrayTypeName() as there is no caller of makeUniqueTypeName() who
> pass tryOriginal = true.
I partially agree with you. But I have one reason to leave
makeUniqueTypeName() separated:
It may be used in other codes with auto generated types. For example, I
think, the DefineRelation routine should choose composite type instead
of using the same name as the table.

> Also looking at other ChooseXXXName()
> functions, we don't care about integer overflow. Is it better to make
> it consistent with them?
Done.

[1]
https://www.postgresql.org/message-id/flat/121e286f-3796-c9d7-9eab-6fb8e0b9c701%40postgrespro.ru

--
Regards
Andrey Lepikhov
Postgres Professional