I get the following error when trying to transform points stored in ST_GEOMETRY EPSG 32198 into WGS 84 EPSG 4326:
ORA-20603: Spatial References are not compatible. ORA-06512: at "SDE.ST_GEOMETRY_SHAPELIB_PKG", line 720 ORA-06512: at "SDE.ST_GEOMETRY_OPERATORS", line 2623
It looks like ST_TRANSFORM is having a hard time to convert NAD 83 EPSG 4269 based projection (like 32198) into WGS 84 EPSG 4326. Which I believe to be a very simple task for any GIS software. The conversion between them, at least in North America should be straight forward.
Weird isn't it?
The work around I found was to use NAD 83 EPSG 4269. sde.st_x(sde.st_transform(a.SHAPE,4269)) sde.st_Y(sde.st_transform(a.shape,4269))