Question: I am using ESRI based GIS software, Postgresql/PostGIS/ArcSDE DB and we have a Mincom Ellipse asset management system.

Currently our all our spatial information regarding asset sites have been recorded as points, this has been versatile for the fact that it accommodates mapping at various scales. Now that we are integrating our Asset Management System with our GIS database the asset management guys want the GIS features to reflect the structure e.g A building footprint as a polygon instead of a point. 

My question in terms of the spatial data management. Should I be maintaining two sets of data? One for the asset representations and then one for various mapping tasks?

Thanks
DB

Answer: 
I suggest you have one table that contains both the polygon and point data. This table would have (at minimum):

* an id column that is a foreign key to the matching asset record,
* a geometry column that contains that polygon geometry and
* a geometry column that contains the point geometry.

Create a trigger that updates the point column based on inserts/changes in the polygon column using st\_pointonsurface.

Create two views, one that has only the polygon columns and one that contains only the point column (include the id column and any others in the views, of course). These views are what you register with SDE.

This way you should be able to worry only about keeping the polygon data up-to-date. If there's no polygon, you can still put in a point. Remember to filter out records with null geometries from the views.
> 
> Do I now have to create a polygon
>  layer for my dams to be used with the
>  asset management system for viewing at
>  1:1,000 then a point layer for mapping
>  purposes when producing a map of the
>  same sites at 1:100,000?
> 
> 
> 

One alternative might be to develop a [custom renderer](http://help.arcgis.com/en/sdk/10.0/arcobjects_net/componenthelp/index.html#//0012000004wn000000) that displays points for dams when zoomed out beyond a certain scale.