Обсуждение: Re: BUG #18923: pg_dump 18beta1 fails to process complex table names

PG Bug reporting form <noreply@postgresql.org> writes:
> I have just run the E-Maj project regression test suite with PG18 beta1 and
> found a pg_dump abort when trying to dump a schema prefixed table having a
> complex name including single quote, double quote and space.

Thanks for the report!  Looks like fetchAttributeStats() is completely
misguided about the appropriate quoting rules for array elements.

            regards, tom lane

Nathan Bossart <nathandbossart@gmail.com> writes:
> I don't think we want to teach appendPGArray() to handle single quotes.

No, that seems quite wrong.  array_in won't de-dup single quotes.

> My first instinct is that we need to build the array with appendPGArray()
> and then append it to the query using appendStringLiteralAH(), as done in
> the attached patch.

Yeah, I think so.  I was confused for a bit because the one extant
user of appendPGArray is getNamespaces which does an additional layer
of quote-doubling via quoteAclUserName.  However, that seems to be because
it's trying to build aclitem[] arrays whose elements will be read by
aclitemin, and that de-dups double quotes.

Wouldn't be a bad idea to add a test case.

            regards, tom lane

On Fri, May 16, 2025 at 3:03 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>
> Yeah, I think so.  I was confused for a bit because the one extant
> user of appendPGArray is getNamespaces which does an additional layer
> of quote-doubling via quoteAclUserName.  However, that seems to be because
> it's trying to build aclitem[] arrays whose elements will be read by
> aclitemin, and that de-dups double quotes.
>

getNamespaces use appendPGArray for object's initial ACL string

getNamespaces
``
nsinfo[i].dacl.initprivs = pstrdup(aclarray->data);
``

and we seems *only* use it dumpACL->buildACLCommands
``
    if (!parsePGArray(baseacls, &baseitems, &nbaseitems))
    {
        free(aclitems);
        free(baseitems);
        return false;
    }
``
parsePGArray didn't handle single-quotes.

I think the above is the reason single-quotes within array elements didn't cause
trouble.

Committed.

-- 
nathan