[Question] How to transform XY LINESTRING into XYZ LINESTRING? about sf HOT 2 CLOSED

additional notes, i can make sure every correct linestring has z values 0. It is because my network street only stored in XY data. I m not pretty sure why after exploding it in QGIS making the geometry has z-values. Also, idk which one the correct solution, either making all object has dim = XYZ or making all object dim = XY but I think both of them would have the same code.

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Hi everyone! I think i found the solution and it just use st_cast and st_zm to convert linestring and drop the z coordinates hence all object has geometrical type LINESTRING and XY coordinate. I apologize for causing a disturbance. Thank you!

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