Hans Forbrich <hforbric_at_yahoo.net> wrote in message news:<6J8Zb.26134$n17.21075_at_clgrps13>...
> FinnE wrote:
> > Hans Forbrich <hforbric_at_yahoo.net> wrote in message news:<s84Zb.30295$D_5.9646_at_edtnps84>...
> >
> >>FinnE wrote:
> >>
> >>>Is it possible to have multiple spatial attributes in a single
> >>>database record in Oracle9i or higher?
> >>
> >>Yes.
> >>
> >>Some orgs use this fact to have high/med/low resolution point
> >>information in a table allowing the front-end app to switch and chose
> >>the appropriate amount of data to transfer.
> >>
> >><elabortion>
> >>What you refer to as 'Spatial attributes' are object types. You can
> >>have any number in a table and each 'appears' as a column.
> >>
> >>Quick def of the spatial object: There are 5 fields
> >>- general type of data indicator,
> >>- coord-system_id (if using projected coord system),
> >>- single point coords (if type indicates it's only a point),
> >>- a list for the 2D/3D/(+added info such as LRS) data points (generally
> >>counter-clockwise),
> >>- a list that indicates at which point gives a new data definition
> >>(polygon starts here, curve starts here, etc.)
> >>
> >><more info source>
> >>There are a number of excellent tutorials in Oracle's OnLine library at
> >>http://Education.oracle.com
> >></more info source>
> >></elabortion>
> >>
> >>HTH
> >>/Hans
> >>
> >>(BTW - no need to cross-post)
> >
> >
> > Where in the oracle documentation does it give you that information?
> > Also do you know - to what precision can Oracle Spatical store arcsec?
> > Erin
>
> In the Spatial documentation. To get to the docco ...
>
> http://docs.oracle.com
> >> the database version you're working on
> >> 'View Library' link
> >> 'List of Books' link
> >> Spatial User's Guide and Reference (about 60% down the page)
>
> The precision depends on the projection, if used, and the version of
> database. However, in general you don't use precision, instead you
> specify the tolerance. (Aside from the 950+ known projections, you can
> also define your own coord system as well, and override tolerance for that.)
>
> As of 9iR2, if using geodetics, your tolerance is specified in meters
> and is generally set at .005 meters. (Converting between defined
> projections and geodetics is accomplished using viewport
> transformations, so you can likely get the data to the arc spec you need).
>
> HTH
> /Hans
I've tried searching both 9iR2 and 10g documentation - it looks like
an oracle table can only have one SDO_GEOMETRY type column. I
couldn't find anywhere where more than one SDO_GEOMETRY
column/attribute was allowed for a record.
Received on Fri Feb 20 2004 - 01:08:33 CST
