Re: Hash support for row types

On 2020-10-20 17:10, Peter Eisentraut wrote:
> On 2020-10-20 01:32, Andres Freund wrote:
>> How does this deal with row types with a field that doesn't have a hash
>> function? Erroring out at runtime could cause queries that used to
>> succeed, e.g. because all fields have btree ops, to fail, if we just have
>> a generic unconditionally present hash opclass?  Is that an OK
>> "regression"?
> 
> Good point.  There is actually code in the type cache that is supposed
> to handle that, so I'll need to adjust that.

Here is an updated patch with the type cache integration added.

To your point, this now checks each fields hashability before 
considering a row type as hashable.  It can still have run-time errors 
for untyped record datums, but that's not something we can do anything 
about.

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