Select SDE.ST_GEOMETRY polylines that have arcs?

Question

Oracle 18c/10.7.1 EGDB:

I have an SDE.ST_GEOMETRY polyline feature class.

Some of the polylines in the feature class have arcs.

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Question:

Is there a way to use Oracle SDE.ST_GEOEMTRY functions to select polylines with arcs?

I've looked through the docs, but haven't been able to find any functions that pertain to segment types.

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Related:

Given the line between points 1 and 2, what is the change in angle to point 3?

Answer 1

I wonder if this would be a possible workaround:

1. Create a field in the feature class called HAS_CURVES.

2. Populate the field in real-time/when a user creates or modifies a feature -- using a Calculation Attribute Rule.

   • Compare $feature.shape_length, which is the true length, including true curves
   • vs.
   • Length($feature), which is the pre-densified length, where true curves have been converted into straight segments. A screenshot of some testing I did: https://i.stack.imgur.com/ilJrg.png
   • If there is a difference between those two values, then that tells us that the line has curves. Use a Calculation Attribute Rule to set the HAS_CURVES field to "Y", or 1, or whatever applies.

3. The HAS_CURVES field would be available to SQL. So we could query on it to find lines with curves.

Disclaimer: It's possible that comparing the those lengths might not work in all scenarios (due to rounding complications, etc.). Testing would be needed.

Related:

• Idea: Determine if line has true curves via SQL (SDE.ST_GEOMETRY in Oracle)
• Idea: hasCurve Arcade geometry property