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CREATE TABLE #test (wkt geometry);
INSERT INTO #test (wkt)
VALUES (geometry::STGeomFromText('LINESTRING (10 100, 15 200, 20 300)', 0))
SELECT * FROM #test;
SELECT *, wkt.STLength() AS Length FROM #test;
| wkt |
|---|
| LINESTRING (10 100, 15 200, 20 300) |
| wkt | Length |
|---|---|
| LINESTRING (10 100, 15 200, 20 300) | 200.249843945008 |