PostGIS Support and Constraints

Updated on 2024-12-18 GMT+08:00

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Supported Data Types

In GaussDB(DWS), PostGIS Extension support the following data types:

box2d
box3d
geometry_dump
geometry
geography
raster

NOTE:

If PostGIS is used by a user other than the creator of the PostGIS, set the following GUC parameters:

SET behavior_compat_options = 'bind_procedure_searchpath';

Supported Operators and Functions

NOTE:

The ST_Intersects function in PostGIS uses a caching strategy that enables a high cache hit ratio for the spatial data structures of foreign tables. When there is a significant disparity in the width between the inner and foreign tables, caching the wide table's data avoid the repeated loading of large objects, leading to significant performance enhancements. Practically, leveraging Join Order Hints to designate a wide table as the foreign table ensures that the execution plan is optimized for such scenarios.

**Table 1** **Operators and functions supported by PostGIS2.4.2**
Category	Function
Management functions	AddGeometryColumn, DropGeometryColumn, DropGeometryTable, PostGIS_Full_Version, PostGIS_GEOS_Version, PostGIS_Liblwgeom_Version, PostGIS_Lib_Build_Date, PostGIS_Lib_Version, PostGIS_PROJ_Version, PostGIS_Scripts_Build_Date, PostGIS_Scripts_Installed, PostGIS_Version, PostGIS_LibXML_Version, PostGIS_Scripts_Released, Populate_Geometry_Columns, UpdateGeometrySRID
Geometry constructors	ST_BdPolyFromText, ST_BdMPolyFromText, ST_Box2dFromGeoHash, ST_GeogFromText, ST_GeographyFromText, ST_GeogFromWKB, ST_GeomCollFromText, ST_GeomFromEWKB, ST_GeomFromEWKT, ST_GeometryFromText, ST_GeomFromGeoHash, ST_GeomFromGML, ST_GeomFromGeoJSON, ST_GeomFromKML, ST_GMLToSQL, ST_GeomFromText, ST_GeomFromWKB, ST_LineFromMultiPoint, ST_LineFromText, ST_LineFromWKB, ST_LinestringFromWKB, ST_MakeBox2D, ST_3DMakeBox, ST_MakeEnvelope, ST_MakePolygon, ST_MakePoint, ST_MakePointM, ST_MLineFromText, ST_MPointFromText, ST_MPolyFromText, ST_Point, ST_PointFromGeoHash, ST_PointFromText, ST_PointFromWKB, ST_Polygon, ST_PolygonFromText, ST_WKBToSQL, ST_WKTToSQL
Geometry accessors	GeometryType, ST_Boundary, ST_CoordDim, ST_Dimension, ST_EndPoint, ST_Envelope, ST_ExteriorRing, ST_GeometryN, ST_GeometryType, ST_InteriorRingN, ST_IsClosed, ST_IsCollection, ST_IsEmpty, ST_IsRing, ST_IsSimple, ST_IsValid, ST_IsValidReason, ST_IsValidDetail, ST_M, ST_NDims, ST_NPoints, ST_NRings, ST_NumGeometries, ST_NumInteriorRings, ST_NumInteriorRing, ST_NumPatches, ST_NumPoints, ST_PatchN, ST_PointN, ST_SRID, ST_StartPoint, ST_Summary, ST_X, ST_XMax, ST_XMin, ST_Y, ST_YMax, ST_YMin, ST_Z, ST_ZMax, ST_Zmflag, ST_ZMin
Geometry editors	ST_AddPoint, ST_Affine, ST_Force2D, ST_Force3D, ST_Force3DZ, ST_Force3DM, ST_Force4D, ST_ForceCollection, ST_ForceSFS, ST_ForceRHR, ST_LineMerge, ST_CollectionExtract, ST_CollectionHomogenize, ST_Multi, ST_RemovePoint, ST_Reverse, ST_Rotate, ST_RotateX, ST_RotateY, ST_RotateZ, ST_Scale, ST_Segmentize, ST_SetPoint, ST_SetSRID, ST_SnapToGrid, ST_Snap, ST_Transform, ST_Translate, ST_TransScale
Geometry outputs	ST_AsBinary, ST_AsEWKB, ST_AsEWKT, ST_AsGeoJSON, ST_AsGML, ST_AsHEXEWKB, ST_AsKML, ST_AsLatLonText, ST_AsSVG, ST_AsText, ST_AsX3D, ST_GeoHash
Operators	&&, &&&, &<, &<\|, &>, <<, <<\|, =, >>, @, \|&>, \|>>, ~, ~=, <->, <#>
Spatial relationships and measurements	ST_3DClosestPoint, ST_3DDistance, ST_3DDWithin, ST_3DDFullyWithin, ST_3DIntersects, ST_3DLongestLine, ST_3DMaxDistance, ST_3DShortestLine, ST_Area, ST_Azimuth, ST_Centroid, ST_ClosestPoint, ST_Contains, ST_ContainsProperly, ST_Covers, ST_CoveredBy, ST_Crosses, ST_LineCrossingDirection, ST_Disjoint, ST_Distance, ST_HausdorffDistance, ST_MaxDistance, ST_DistanceSphere, ST_DistanceSpheroid, ST_DFullyWithin, ST_DWithin, ST_Equals, ST_HasArc, ST_Intersects, ST_Length, ST_Length2D, ST_3DLength, ST_Length_Spheroid, ST_Length2D_Spheroid, ST_3DLength_Spheroid, ST_LongestLine, ST_OrderingEquals, ST_Overlaps, ST_Perimeter, ST_Perimeter2D, ST_3DPerimeter, ST_PointOnSurface, ST_Project, ST_Relate, ST_RelateMatch, ST_ShortestLine, ST_Touches, ST_Within
Geometry processing	ST_Buffer, ST_BuildArea, ST_Collect, ST_ConcaveHull, ST_ConvexHull, ST_CurveToLine, ST_DelaunayTriangles, ST_Difference, ST_Dump, ST_DumpPoints, ST_DumpRings, ST_FlipCoordinates, ST_Intersection, ST_LineToCurve, ST_MakeValid, ST_MemUnion, ST_MinimumBoundingCircle, ST_Polygonize, ST_Node, ST_OffsetCurve, ST_RemoveRepeatedPoints, ST_SharedPaths, ST_Shift_Longitude, ST_Simplify, ST_SimplifyPreserveTopology, ST_Split, ST_SymDifference, ST_Union, ST_UnaryUnion
Linear referencing	ST_LineInterpolatePoint, ST_LineLocatePoint, ST_LineSubstring, ST_LocateAlong, ST_LocateBetween, ST_LocateBetweenElevations, ST_InterpolatePoint, ST_AddMeasure
Miscellaneous functions	ST_Accum, Box2D, Box3D, ST_Expand, ST_Extent, ST_3Dextent, Find_SRID, ST_MemSize
Exceptional functions	PostGIS_AddBBox, PostGIS_DropBBox, PostGIS_HasBBox
Raster Management Functions	AddRasterConstraints, DropRasterConstraints, AddOverviewConstraints, DropOverviewConstraints, PostGIS_GDAL_Version, PostGIS_Raster_Lib_Build_Date, PostGIS_Raster_Lib_Version, and ST_GDALDrivers, and UpdateRasterSRID
Raster Constructors	ST_AddBand, ST_AsRaster, ST_Band, ST_MakeEmptyRaster, ST_Tile, and ST_FromGDALRaster
Raster Accessors	ST_GeoReference, ST_Height, ST_IsEmpty, ST_MetaData, ST_NumBands, ST_PixelHeight, ST_PixelWidth, ST_ScaleX, ST_ScaleY, ST_RasterToWorldCoord, ST_RasterToWorldCoordX, ST_RasterToWorldCoordY, ST_Rotation, ST_SkewX, ST_SkewY, ST_SRID, ST_Summary, ST_UpperLeftX, ST_UpperLeftY, ST_Width, ST_WorldToRasterCoord, ST_WorldToRasterCoordX, ST_WorldToRasterCoordY
Raster Band Accessors	ST_BandMetaData, ST_BandNoDataValue, ST_BandIsNoData, ST_BandPath, ST_BandPixelType, and ST_HasNoBand
Raster Pixel Accessors and Setters	ST_PixelAsPolygon, ST_PixelAsPolygons, ST_PixelAsPoint, ST_PixelAsPoints, ST_PixelAsCentroid, ST_PixelAsCentroids, ST_Value, ST_NearestValue, ST_Neighborhood, ST_SetValue, ST_SetValues, ST_DumpValues, and ST_PixelOfValue
Raster Editors	ST_SetGeoReference, ST_SetRotation, ST_SetScale, ST_SetSkew, ST_SetSRID, ST_SetUpperLeft, ST_Resample, ST_Rescale, ST_Reskew, and ST_SnapToGrid, ST_Resize, and ST_Transform
Raster Band Editors	ST_SetBandNoDataValue and ST_SetBandIsNoData
Raster Band Statistics and Analytics	ST_Count, ST_CountAgg, ST_Histogram, ST_Quantile, ST_SummaryStats, ST_SummaryStatsAgg, and ST_ValueCount
Raster Outputs	ST_AsBinary, ST_AsGDALRaster, ST_AsJPEG, ST_AsPNG, and ST_AsTIFF
Raster Processing	ST_Clip, ST_ColorMap, ST_Intersection, ST_MapAlgebra, ST_Reclass, and ST_Union ST_Distinct4ma, ST_InvDistWeight4ma, ST_Max4ma, ST_Mean4ma, ST_Min4ma, ST_MinDist4ma, ST_Range4ma, ST_StdDev4ma, and ST _Sum4ma, ST_Aspect, ST_HillShade, ST_Roughness, ST_Slope, ST_TPI, ST_TRI, Box3D, ST_ConvexHull, ST_DumpAsPolygons, and ST_ Envelope, ST_MinConvexHull, ST_Polygon, ST_Contains, ST_ContainsProperly, ST_Covers, ST_CoveredBy, ST_Disjoint, ST_Intersects, and ST_Overlaps, ST_Touches, ST_SameAlignment, ST_NotSameAlignmentReason, ST_Within, ST_DWithin, and ST_DFullyWithin
Raster Operators	&&, &<, &>, =, @, ~=, and ~

**Table 2** **Operators and functions supported by PostGIS3.2.2**
Category	Function
Management functions	AddGeometryColumn, DropGeometryColumn, DropGeometryTable, PostGIS_Full_Version, PostGIS_GEOS_Version, PostGIS_Liblwgeom_Version, PostGIS_Lib_Build_Date, PostGIS_Lib_Version, PostGIS_PROJ_Version, PostGIS_Scripts_Build_Date, PostGIS_Scripts_Installed, PostGIS_Version, PostGIS_LibXML_Version, PostGIS_Scripts_Released, Populate_Geometry_Columns, UpdateGeometrySRID, PostGIS_Libprotobuf_Version, PostGIS_Wagyu_Version
Geometry constructors	ST_BdPolyFromText, ST_BdMPolyFromText, ST_Box2dFromGeoHash, ST_GeneratePoints, ST_GeogFromText, ST_GeographyFromText, ST_GeogFromWKB, ST_GeomCollFromText, ST_GeomFromEWKB, ST_GeomFromEWKT, ST_GeometryFromText, ST_GeomFromGeoHash, ST_GeomFromGML, ST_GeomFromGeoJSON, ST_GeomFromKML, ST_GMLToSQL, ST_GeomFromText, ST_GeomFromWKB, ST_LineFromMultiPoint, ST_LineFromText, ST_LineFromWKB, ST_LinestringFromWKB, ST_MakeBox2D, ST_3DMakeBox, ST_MakeEnvelope, ST_MakePolygon, ST_MakePoint, ST_MakePointM, ST_MLineFromText, ST_MPointFromText, ST_MPolyFromText, ST_Point, ST_Points, ST_PointFromGeoHash, ST_PointFromText, ST_PointFromWKB, ST_Polygon, ST_PolygonFromText, ST_WKBToSQL, ST_WKTToSQL, Geography_Distance_Knn, Geometry_Distance_Cpa, Geometry_Hash, ST_3Dlineinterpolate, ST_AsEncodedPolyline
Geometry accessors	GeometryType, ST_Boundary, ST_CoordDim, ST_Dimension, ST_EndPoint, ST_Envelope, ST_ExteriorRing, ST_GeometryN, ST_GeometryType, ST_InteriorRingN, ST_IsClosed, ST_IsCollection, ST_IsEmpty, ST_IsPolygonCCW, ST_IsPolygonCW, ST_IsRing, ST_IsSimple, ST_IsValid, ST_IsValidReason, ST_IsValidDetail, ST_M, ST_NDims, ST_NPoints, ST_NRings, ST_NumGeometries, ST_NumInteriorRings, ST_NumInteriorRing, ST_NumPatches, ST_NumPoints, ST_PatchN, ST_PointN, ST_SRID, ST_StartPoint, ST_Summary, ST_X, ST_XMax, ST_XMin, ST_Y, ST_YMax, ST_YMin, ST_Z, ST_ZMax, ST_Zmflag, ST_ZMin, ST_Wrapx, ST_Asmvt
Geometry editors	ST_AddPoint, ST_Affine, ST_Force2D, ST_Force3D, ST_Force3DZ, ST_Force3DM, ST_Force4D, ST_ForceCollection, ST_ForcePolygonCCW, ST_ForcePolygonCW, ST_ForceSFS, ST_ForceRHR, ST_LineMerge, ST_CollectionExtract, ST_CollectionHomogenize, ST_Multi, ST_Normalize, ST_RemovePoint, ST_Reverse, ST_Rotate, ST_RotateX, ST_RotateY, ST_RotateZ, ST_Scale, ST_Segmentize, ST_SetPoint, ST_SetSRID, ST_SnapToGrid, ST_Snap, ST_Transform, ST_Translate, ST_TransScale, ST_AsmvtGeom, ST_isvalidTrajectory, ST_linefromencodedpolyline, ST_lineinterpolatepoints, ST_MaximuminScribedCircle, ST_OrientedEnvelope, ST_QuantizeCoordinates, ST_ReducePrecision, ST_Scroll, ST_SetEffectiveArea, ST_simplifyvw, ST_square, ST_squaregrid, ST_Swapordinates, ST_Voronoilines, ST_VoronoiPolygons
Geometry outputs	ST_AsBinary, ST_AsEWKB, ST_AsEWKT, ST_AsGeoJSON, ST_AsGML, ST_AsHEXEWKB, ST_AsKML, ST_AsLatLonText , ST_AsSVG, ST_AsText, ST_AsTwkb, ST_AsX3D, ST_GeoHash, Json, Jsonb, ST_GeomfromGeojson
Operators	&& , &&& , &< , &<\|, &> , << , <<\|, =, >> , @ , \|&> , \|>> , ~, ~=, <-> , <#> , <-> , \|=\|, <<->>
Spatial relationships and measurements	ST_3DClosestPoint, ST_3DDistance, ST_3DDWithin, ST_3DDFullyWithin, ST_3DIntersects, ST_3DLongestLine, ST_3DMaxDistance, ST_3DShortestLine, ST_Area, ST_Azimuth, ST_Centroid, ST_ClosestPoint, ST_Contains, ST_ContainsProperly, ST_Covers, ST_CoveredBy, ST_Crosses, ST_LineCrossingDirection, ST_Disjoint, ST_Distance, ST_HausdorffDistance, ST_MaxDistance, ST_DistanceSphere, ST_DistanceSpheroid, ST_DFullyWithin, ST_DWithin, ST_Equals, ST_HasArc, ST_Intersects, ST_Length, ST_Length2D, ST_3DLength, ST_LengthSpheroid, ST_Length2DSpheroid, ST_LongestLine, ST_MinimumBoundingRadius, ST_OrderingEquals, ST_Overlaps, ST_Perimeter, ST_Perimeter2D, ST_3DPerimeter, ST_PointOnSurface, ST_Project, ST_Relate, ST_RelateMatch, ST_ShortestLine, ST_Touches, ST_Within, _ST_DistancerectTree, _ST_DistancerectTreeCached, _ST_SorTableHash
Geometry processing	ST_Buffer, ST_BuildArea, ST_ClipByBox2D, ST_ClusterDBSCAN, ST_ClusterIntersecting, ST_ClusterKMeans, ST_ClusterWithin, ST_Collect, ST_ConcaveHull, ST_ConvexHull, ST_CurveToLine, ST_DelaunayTriangles, ST_Difference, ST_Dump, ST_DumpPoints, ST_DumpRings, ST_FlipCoordinates, ST_Intersection, ST_LineToCurve, ST_MakeValid, ST_MemUnion, ST_MinimumBoundingCircle, ST_Polygonize, ST_Node, ST_OffsetCurve, ST_RemoveRepeatedPoints, ST_SharedPaths, ST_ShiftLongitude, ST_Simplify, ST_SimplifyPreserveTopology, ST_Split, ST_Subdivide, ST_SymDifference, ST_Union, ST_UnaryUnion, ST_BoundingDiagonal, ST_ChaikinsMoothing, ST_ClosestPointofApproach, ST_CollectionExtract, ST_CPAwithin, ST_DistanceCPA, ST_DumpSegments, ST_EstimatedExtent, ST_Filterbym, ST_SetEffectiveArea, ST_Forcecurve
Linear referencing	ST_LineInterpolatePoint, ST_LineLocatePoint, ST_LineSubstring, ST_LocateAlong, ST_LocateBetween, ST_LocateBetweenElevations, ST_InterpolatePoint, ST_AddMeasure
Miscellaneous functions	Array_Agg, Box2D, Box3D, ST_Expand, ST_Extent, ST_3Dextent, Find_SRID, ST_MemSize
Exceptional functions	PostGIS_AddBBox, PostGIS_DropBBox, PostGIS_HasBBox

Spatial Indexes

In GaussDB(DWS), PostGIS Extension supports Generalized Search Tree (GIST) spatial indexes. This index type is inapplicable to partitioned tables. Different from B-tree indexes, GIS indexes are adaptable to all kinds of irregular data structures, which can effectively improve the retrieval efficiency for geometry and geographic data.

Run the following command to create a GiST index:

    
       CREATE INDEX indexname ON tablename USING GIST ( geometryfield );

Extension Constraints

Only row-store tables are supported. Column-store indexes are not supported.
Only Oracle-compatible databases are supported.
The topology object management module, Topology, is not supported.
BRIN indexes are not supported.
The spatial_ref_sys table can only be queried during scale-out.

Plug-in Upgrade Compatibility

When upgrading from PostGIS 2.4.2 to 3.2.2, note that certain functions may become incompatible or not fully forward compatible. This can lead to inconsistencies in the functionality before and after the upgrade. Therefore, it is necessary to assess the impact of upgrade incompatibility on your services.

The following table provides compatibility details for related functions.

Category	PostGIS 2.4.2	PostGIS 3.2.2
Added functions in 3.2.2	N/A	ST_IsPolygonCW(geometry)
	N/A	ST_IsPolygonCCW(geometry)
	N/A	ST_PointInsideCircle(geometry,float8,float8,float8)
	N/A	ST_ForcePolygonCW(geometry)
	N/A	ST_ForcePolygonCCW(geometry)
	N/A	ST_Normalize(geom geometry)
	N/A	ST_AsTWKB(geom geometry, prec int4 default 0, prec_z int4 default 0, prec_m int4 default 0, with_sizes boolean default false, with_boxes boolean default false)
	N/A	ST_AsTWKB(geom geometry[], ids bigint[], prec int4 default 0, prec_z int4 default 0, prec_m int4 default 0, with_sizes boolean default false, with_boxes boolean default false)
	N/A	ST_MakeLine (geometry[])
	N/A	ST_TileEnvelope(zoom integer, x integer, y integer, bounds geometry DEFAULT 'SRID=3857;LINESTRING(-20037508.342789244 -20037508.342789244, 20037508.342789244 20037508.342789244)'::geometry, margin float8 DEFAULT 0.0)
	N/A	ST_ClusterIntersecting(geometry[])
	N/A	ST_ClusterWithin(geometry[], float8)
	N/A	ST_ClusterDBSCAN (geometry, eps float8, minpoints int)
	N/A	ST_Scale(geometry,geometry,origin geometry)
	N/A	ST_GeneratePoints(area geometry, npoints integer, seed integer)
	N/A	ST_FrechetDistance(geom1 geometry, geom2 geometry, float8 default -1)
	N/A	ST_Points(geometry)
	N/A	ST_ClipByBox2d(geom geometry, box box2d)
	N/A	ST_Subdivide(geom geometry, maxvertices integer DEFAULT 256, gridSize float8 DEFAULT -1.0)
	N/A	ST_ClusterIntersecting (geometry)
	N/A	ST_ClusterWithin (geometry, float8)
	N/A	ST_ClusterKMeans(geom geometry, k integer, max_radius float8 default null)
	N/A	ST_AsText(geometry, int4)
	N/A	ST_AsEWKT(geography, int4)
	N/A	_ST_CoveredBy(geog1 geography, geog2 geography)
	N/A	ST_Point(float8, float8, srid integer)
Functions no longer supported in 3.2.2	ST_3DLength_spheroid(geometry, spheroid)	N/A
	ST_length2d_spheroid(geometry, spheroid)	N/A
	ST_locate_between_measures(geometry, float8, float8)	N/A
	ST_locate_along_measure(geometry, float8)	N/A
	ST_Buffer(geometry,float8,text)	N/A
	ST_GeneratePoints(area geometry, npoints integer)	N/A
	ST_Combine_BBox(box3d,geometry)	N/A
	ST_Combine_BBox(box2d,geometry)	N/A
	pgis_abs_in(cstring)	N/A
	pgis_abs_out(pgis_abs)	N/A
	pgis_abs ( internallength = 16, input = pgis_abs_in, output = pgis_abs_out, alignment = double)	N/A
	ST_MemUnion(geometry)	N/A
	pgis_geometry_accum_finalfn(pgis_abs)	N/A
	ST_MakeLine (geometry)	N/A
	ST_Accum (geometry)	N/A
	ST_Accum (geometry)	N/A
	_ST_AsKML(int4,geometry, int4, text)	N/A
	ST_MemUnion(geometry)	N/A
	_ST_AsGeoJson(int4, geometry, int4, int4)	N/A
	ST_AsGeoJson(gj_version int4, geom geometry, maxdecimaldigits int4 DEFAULT 15, options int4 DEFAULT 0)	N/A
	_ST_DWithin(geography, geography, float8, boolean)	N/A
	ST_point_inside_circle(geometry,float8,float8,float8)	N/A
	ST_CurveToLine(geometry)	N/A
	ST_Shift_Longitude(geometry)	Use ST_ShiftLongitude instead.
	ST_find_extent(text,text,text) and ST_find_extent(text,text)	Use ST_FindExtent instead.
	ST_mem_size(geometry)	Use ST_MemSize instead.
	ST_length_spheroid(geometry, spheroid)	Use ST_LengthSpheroid instead.
	ST_distance_spheroid(geom1 geometry, geom2 geometry,spheroid)	Use ST_DistanceSpheroid instead.
	ST_force_2d(geometry)	Use ST_Force2D instead.
	ST_force_3dz(geometry)	Use ST_Force3DZ instead.
	ST_force_3d(geometry)	Use ST_Force3D instead.
	ST_force_3dm(geometry)	Use ST_Force3DM instead.
	ST_force_4d(geometry)	Use ST_Force4D instead.
	ST_force_collection(geometry)	Use ST_ForceCollection instead.
	ST_line_locate_point(geom1 geometry, geom2 geometry)	Use ST_LineLocatePoint instead.
	ST_line_interpolate_point(geometry, float8)	Use ST_LineInterpolatePoint instead.
	ST_Buffer(geometry,float8)	Use ST_Buffer instead.
Functions with parameter type changed in 3.2.2	pgis_geometry_accum_transfn(pgis_abs, geometry)	pgis_geometry_accum_transfn(internal, geometry)
	pgis_geometry_accum_transfn(pgis_abs, geometry, float8)	pgis_geometry_accum_transfn(internal, geometry, float8)
	pgis_geometry_accum_transfn(pgis_abs, geometry, float8, int)	pgis_geometry_accum_transfn(internal, geometry, float8, int)
	pgis_geometry_union_finalfn(pgis_abs)	pgis_geometry_union_finalfn(internal)
	pgis_geometry_collect_finalfn(pgis_abs)	pgis_geometry_collect_finalfn(internal)
	pgis_geometry_polygonize_finalfn(pgis_abs)	pgis_geometry_polygonize_finalfn(internal)
	pgis_geometry_clusterintersecting_finalfn(pgis_abs)	pgis_geometry_clusterintersecting_finalfn(internal)
	ST_Union (geometry)	ST_Union (geometry)
	ST_Collect (geometry)	ST_Collect (geometry)
	ST_Buffer(geometry,float8,integer)	ST_Buffer(geom geometry, radius float8, quadsegs integer)
Functions with API changed in 3.2.2	ST_AsKML(version int4, geom geometry, maxdecimaldigits int4 DEFAULT 15, nprefix text DEFAULT null)	ST_AsKML(geom geometry, maxdecimaldigits int4 DEFAULT 15, nprefix TEXT default ' ')
	ST_AsKML(geom geometry, maxdecimaldigits int4 DEFAULT 15)	ST_AsKML(geom geometry, maxdecimaldigits int4 DEFAULT 15, nprefix TEXT default ' ')
	ST_AsKML(version int4, geom geometry, maxdecimaldigits int4 DEFAULT 15, nprefix text DEFAULT null)	ST_AsGML(version int4, geog geography, maxdecimaldigits int4 DEFAULT 15, options int4 DEFAULT 0, nprefix text DEFAULT 'gml', id text DEFAULT '')
Functions with default parameters changed in 3.2.2	ST_SymDifference(geom1 geometry, geom2 geometry)	ST_SymDifference(geom1 geometry, geom2 geometry, gridSize float8 DEFAULT -1.0)
	ST_UnaryUnion(geometry)	ST_UnaryUnion(geometry, gridSize float8 DEFAULT -1.0)
	ST_AsGeoJson(geom geometry, maxdecimaldigits int4 DEFAULT 15, options int4 DEFAULT 0)	ST_AsGeoJson(geom geometry, maxdecimaldigits int4 DEFAULT 9, options int4 DEFAULT 8)
	ST_Buffer(geometry,float8,cstring)	ST_Buffer(geom geometry, radius float8, options text DEFAULT ' ')
	_ST_DWithin(geography, geography, float8, boolean)	_ST_DWithin(geog1 geography, geog2 geography, tolerance float8, use_spheroid boolean DEFAULT true)
	ST_IsValidDetail(geometry)	ST_IsValidDetail(geom geometry, flags int4 DEFAULT 0)
	ST_CurveToLine(geom geometry, tol float8, toltype integer, flags integer)	ST_CurveToLine(geom geometry, tol float8 DEFAULT 32, toltype integer DEFAULT 0, flags integer DEFAULT 0)
Functions supported hash join and merge join in 3.2.2	OPERATOR =	OPERATOR =
Functions with commutor undefined in 3.2.2	OPERATOR &< ,OPERATOR &<\|,OPERATOR \|&>	OPERATOR &< ,OPERATOR &<\|,OPERATOR \|&>