Re: Busted(?) optimization in ATAddForeignKeyConstraint

On 2020-01-24 01:21, Thomas Munro wrote:
> On Fri, Jan 24, 2020 at 11:12 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> I happened to notice this comment in the logic in
>> ATAddForeignKeyConstraint that tries to decide if it can skip
>> revalidating a foreign-key constraint after a DDL change:
>>
>>               * Since we require that all collations share the same notion of
>>               * equality (which they do, because texteq reduces to bitwise
>>               * equality), we don't compare collation here.
>>
>> Hasn't this been broken by the introduction of nondeterministic
>> collations?
> 
> Similar words appear in the comment for ri_GenerateQualCollation().

The calls to this function are all conditional on 
!get_collation_isdeterministic().  The comment should perhaps be changed.

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