Slim down the size of geometries with ST_Simplify. Also learn about ST_SimplifyVW, ST_RemoveRepeatedPoints, ST_SnapToGrid, ST_ReducePrecision, and ST_CoveranceClean to make your PostGIS as snappy as ever.

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PostGIS offers multiple geometry simplification functions to reduce vertex count and improve performance. ST_Simplify uses Douglas-Peuker algorithm for line simplification, while ST_SimplifyVW applies Visvalingam-Whyatt for better polygon shape preservation. ST_ReducePrecision snaps to a grid while maintaining validity, unlike ST_SnapToGrid which can create invalid geometries. For shared boundaries, ST_CoverageClean and ST_CoverageSimplify handle groups of polygons while preserving topology. Combining techniques like ST_ReducePrecision with ST_Simplify often yields optimal results.

PostGIS Performance: Simplification