Re: [HACKERS] Replication vs. float timestamps is a disaster

On 02/22/2017 10:21 AM, Jim Nasby wrote:
> On 2/22/17 9:12 AM, Andres Freund wrote:
>>> That would allow an in-place upgrade of
>>> a really large cluster. A user would still need to modify their code
>>> to use
>>> the new type.
>>>
>>> Put another way: add ability for pg_upgrade to change the type of a
>>> field.
>>> There might be other uses for that as well.
>> Type oids are unfortunately embedded into composite and array type data
>> - we can do such changes for columns themselves, but it doesn't work if
>> there's any array/composite members containing the to-be-changed type
>> that are used as columns.
>
> Only in the catalog though, not the datums, right? I would think you
> could just change the oid in the catalog the same as you would for a
> table column.

No, in the datums.

cheers

andrew

-- 
Andrew Dunstan                https://www.2ndQuadrant.com
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