This is not true, because the script should return COVERS, the example in script is a polygon and the line that is compared with SDO_GEOM.RELATE is one side of the polygon, following the concepts:
- COVERS: The interior of one object is completely contained in the interior or the boundary of the other object and their boundaries intersect.
- TOUCH: The boundaries intersect but the interiors do not intersect.
The line is completely contained in the boundary of the polygon, that is why the result must be COVERS not TOUCH
It seems there is a doc bug on COVERS.
For COVERS, the interior of A and the interior of B have to intersect.