[postgis-devel] about interger storage

[Martin Davis]

Why do you think integer storage will provide better accuracy,
integrity, and speed?

- accuracy is a function of your data
- if you are concerned about *precision*, then just having the database
automatically force everything into a fixed precision model doesn't
really address all concerns. You really need to round your data
yourself, and deal explicitly with any data collapse issues
- speed - well, in theory yes, since you are shipping half the data over
the wire. But have you measured this? There's a lot more involved than
raw wire speed.

A major downside of integer storage IMO is the need to specify your data
extent explicity up front. And the need to constantly transform between
integer and the external coordinate system (in floating point) is a
major pain.

xie jiong wrote:
> Hi everyone:
> Does postgis support interger storage? We are thinking about
> conversion from floating point real¨Cworld units to positive integer
> units for storage in the database to provide better data accuracy,data
> integrity,and processing speed as ArcSDE do. Are there any possible
> and difficulties of doing so? Dose Geos support it? As far as I know,
> spatial databases such as Oralce spatial don't use it but I think it
> will really improve performance and low down space. Any idea?
> Jiong
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-- 
Martin Davis
Senior Technical Architect
Refractions Research, Inc.
(250) 383-3022