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ES|QL ST_SIMPLIFYPRESERVETOPOLOGY function

Embedded
geometry
Expression of type geo_point, geo_shape, cartesian_point or cartesian_shape. If null, the function returns null.
tolerance

Tolerance for the geometry simplification, in the units of the input SRS

Simplifies the input geometry by applying a topology-preserving variant of the Douglas-Peucker algorithm with a specified tolerance. Vertices that fall within the tolerance distance from the simplified shape are removed. Unlike ST_SIMPLIFY, the resulting geometry is guaranteed to be topologically valid.

geometry tolerance result
cartesian_point double cartesian_point
cartesian_point float cartesian_point
cartesian_point integer cartesian_point
cartesian_point long cartesian_point
cartesian_shape double cartesian_shape
cartesian_shape float cartesian_shape
cartesian_shape integer cartesian_shape
cartesian_shape long cartesian_shape
geo_point double geo_point
geo_point float geo_point
geo_point integer geo_point
geo_point long geo_point
geo_shape double geo_shape
geo_shape float geo_shape
geo_shape integer geo_shape
geo_shape long geo_shape 
ROW wkt = "POLYGON ((7.998 53.827, 9.470 53.068, 15.754 53.801, 16.523 57.160, 11.162 57.868, 8.064 57.445, 6.219 55.317, 7.998 53.827))"
| EVAL simplified = ST_SIMPLIFYPRESERVETOPOLOGY(TO_GEOSHAPE(wkt), 0.7)
wkt:keyword simplified:geo_shape
POLYGON ((7.998 53.827, 9.470 53.068, 15.754 53.801, 16.523 57.160, 11.162 57.868, 8.064 57.445, 6.219 55.317, 7.998 53.827)) POLYGON ((6.219 55.317, 9.47 53.068, 15.754 53.801, 16.523 57.16, 8.064 57.445, 6.219 55.317))