Re: [BUGS] numerics lose scale and precision in views of unions

On Thu, Aug 10, 2006 at 09:20:09AM -0400, mark(at)mark(dot)mielke(dot)cc wrote:
> Mathematically, 1.0 = 0.9500... -> 1.05000...
>
> In theory, B-Tree could be fine with this. As long as the operators
> for =, <>, <, and > are made to consistently understand this principle.
> For example:
>
> 1.0 = 0.95
> 1.0 = 1.05
> 1.0 <> 0.94
> 1.0 <> 1.06
> 0.94 < 1.0
> 1.06 > 1.0
>
> I'm not sure that it warrants being changed, though. Storing mixed
> precision values in a column and expecting the database to understand
> rounding rules does not appeal to me. Too magical.

I take this back. It's magical enough to be impossible.

If 1.0 is inserted, and then 1.05, it could consider them 'equal' and
put them together. If 1.1 and 1.14 were inserted, they could be 'equal'
and put together. Then an insertion of '1' would have to re-group them
all together, making the B-Tree ineffective.

So - taking back what I say above.

Cheers,
mark

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