Re: Column storage positions - Mailing list pgsql-hackers

From Andrew Dunstan
Subject Re: Column storage positions
Date
Msg-id 45DC71C2.2090400@dunslane.net
Whole thread Raw
In response to Re: Column storage positions  ("Florian G. Pflug" <fgp@phlo.org>)
Responses Re: Column storage positions  ("Florian G. Pflug" <fgp@phlo.org>)
List pgsql-hackers
Florian G. Pflug wrote:
>
> I think you'd want to have a flag per field that tell you if the user
> has overridden the storage pos for that specific field. Otherwise,
> the next time you have to chance to optimize the ordering, you might
> throw away changes that the admin has done on purpose. The same hold
> true for a pg_dump/pg_reload cycle. If none of the fields had their
> storage order changed manually, you'd want to reoder them optimally
> at dump/reload time. If, however, the admin specified an ordering, you'd
> want to preserve that.
>

I don't think users should be monkeying with the storage position at 
all. Decisions about that should belong to the engine, not to users. 
Providing a user tweakable knob for this strikes me as a large footgun, 
as well as requiring all sorts of extra checks along the lines you are 
talking of.

cheers

andrew


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