Regarding SDE.ST_GEOMETRY shape object columns (Oracle):
Rumor has it, true curve info (aka CAD blob data) is stored separately from ST_GEOMETRY info — all within the same shape object/column. In other words, if we query the geometry via ST_GEOMETRY functions, we don't have access to true curve data, since it's stored in a separate object attribute (an LOB attribute).
(I imagine the wording above is wrong, but that's because I don't have any documentation to reference.)
Could information about the above be added to the docs? Otherwise, I'm just fumbling around in the dark.
I know the usual suspects are likely to say, "You can't access the CAD blob via ST_GEOMETRY anyway, so it's a moot point." That might be, but I still need to understand how it's been set up...so I can understand what the limitations are and how to work around them. For example, I need to understand how ST_GEOMETRY pre-densifies the true curves into straight segments. What logic is used for the pre-densification?
Edit - Related: Why did a polygon lose 76 sqft (Shape.Area) when exporting from Oracle ST_Geometery to File GDB?
(merged from a separate idea)
It would be helpful if documentation could be added about about curves and CAD BLOBs in ST_Geometry.
For example, expand on details like this:
From @ShannonShields
Features with curve geometry/circular arcs have two representations in enterprise geodatabases. The ST_Geometry shape stores a densified arc version of the geometry, and the true curve is stored in a blob format read by ArcGIS, but not by the DBMS.
Some related GIS Stack Exchange posts:
https://gis.stackexchange.com/search?q=%5Bst-geometry%5D+cad
@Bud I have merged your two posts so that both of your comments are preserved in the same space.
Thanks as always for your ideas!
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