[fdo-internals] FDO RFC 16 - FDO Provider for SQLite

Frank Warmerdam warmerdam at pobox.com
Mon Mar 24 00:52:17 EDT 2008


Jason Birch wrote:
> Any chance that I could convince you guys to use "geometry_type" (or
> something else) rather than "type" in the table definition?  Using a generic
> term like "type" is just bad karma from a database design standpoint...
> 
> If you did this, would you feel the need to go to the integer definition for
> this field and use the numeric codes in the spec?  And is there a strong
> reason for deviating from this, other than not supporting all of the types?

Jason Birch wrote:
 > Oh, and in the embrace and extend track... is there a reason we couldn't use
 > storage_type in preference to geometry_format, and extend it with two
 > additional codes (2, 3 or maybe 9001, 9002) for FGF and WKT?

Jason,

The "type" field is based on what I saw in PostGIS.  I'm not sure if it is
described in the SF spec or not.  But, without a fairly specific reason to
be different, I'd prefer to match what PostGIS does so it is easy for folks
who already work with it to understand what is being done in SQLite.  So,
based on that I'm not *keen* on changing the field name or the contents.

There are various reasons I don't like using integer codes in the field.
First, it is different than PostGIS.  Second, I don't know what sorts of
values to use for odd things like FGF curves.  Third, I find the strings
more self-descriptive than integer codes.

I didn't really understand why you preferred storage_type to geometry_format.
The geometry_format is unique to the sqlite proposal as far as I know, so
if there is a reason for storage_type instead, I'd be quite open to a
change.  Does this align better with some other format?

BTW, the naming, etc proposed for stuff in sqlite could just as easily
be applied to any other non-spatial RDBMS type environment.

Best regards,
-- 
---------------------------------------+--------------------------------------
I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | President OSGeo, http://osgeo.org



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