Re: Separate the attribute physical order from logical order - Mailing list pgsql-hackers

From Tom Lane
Subject Re: Separate the attribute physical order from logical order
Date
Msg-id 2747122.1656447773@sss.pgh.pa.us
Whole thread Raw
In response to Re: Separate the attribute physical order from logical order  (Peter Geoghegan <pg@bowt.ie>)
List pgsql-hackers
Peter Geoghegan <pg@bowt.ie> writes:
> On Tue, Jun 28, 2022 at 11:47 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> Now you do need something that will make the three meanings different
>> in order to test that step.  But I'd suggest some bit of throwaway code
>> that just assigns randomly different logical and physical orders.

> That seems like a good idea. Might also make sense to make the
> behavior configurable via a developer-only GUC, to enable exhaustive
> tests that use every possible permutation of physical/logical mappings
> for a given table.
> Perhaps the random behavior itself should work by selecting a value
> for the GUC at various key points via a PRNG. During CREATE TABLE, for
> example. This approach could make it easier to reproduce failures on the
> buildfarm.

Yeah, it can't be *too* random or debugging failures will be a nightmare.
My point is just to not spend a lot of engineering on this part, because
it won't be a long-term user feature.

            regards, tom lane



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