Re: pg_class.relpages/allvisible probably shouldn't be a int4

On May 9, 2014 10:37:49 PM CEST, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>Andres Freund <andres(at)2ndquadrant(dot)com> writes:
>> That's nothing for 9.4 anymore, but shouldn't we make
>pg_class.relpages
>> a int8 (sounds slightly better than float to me) or somesuch?
>
>No; those are really BlockNumbers, and have always been. float4 would
>lose information and float8 or int8 would waste space. If we had an
>unsigned int type it'd be better. I suppose we could declare them as
>OID,
>but that would probably confuse people no end.

Well negative numbers aren't great either. Although admittedly it's not yet affecting many...

I think the waste of storing 2*4 additional bytes isn't going to hurt much.
And adding a proper unsigned type doesn't sound like a small amount of work. Not to speak of overloading troubles....
I realize they are block numbers and casted in most places - that's why the overflow doesn't seem to cause too many troubles.

Andres

--
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Andres Freund http://www.2ndQuadrant.com/
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