Re: Proposal: In-Place upgrade concept

Tom Lane wrote:

> 
>> I do not expect that old code will work with new index structure. I want 
>> to keep both implementation and old index will be processed by old code 
>> and new one will be processed by new implementation. Each will have 
>> different OID and pg_class.relam will point to correct implementation. 
> 
> I don't think it's quite that easy when you consider user-defined
> datatypes.  Where are you going to get two sets of opclasses from?

Good point. I think if new index implementation does not change meaning 
of strategy and function number old opclasses set could be used. And it 
is only for new created or recreated indexes. Existing indexes will work 
fine with old opclasses set.

        Zdenek