PostGIS Support and Constraints¶
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¶
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 ~ |
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.
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.