ST_AsBinary Return the Well-Known Binary (WKB) representation of the geometry/geography without SRID meta data. bytea ST_AsBinary geometry g1 bytea ST_AsBinary geography g1 bytea ST_AsBinary geometry g1 text NDR_or_XDR Returns the Well-Known Binary representation of the geometry. There are 2 variants of the function. The first variant takes no endian encoding parameter and defaults to little endian. The second variant takes a second argument denoting the encoding - using little-endian ('NDR') or big-endian ('XDR') encoding. This is useful in binary cursors to pull data out of the database without converting it to a string representation. The WKB spec does not include the SRID. To get the OGC WKB with SRID format use ST_AsEWKB ST_AsBinary is the reverse of for geometry. Use to convert to a postgis geometry from ST_AsBinary representation. The default behavior in PostgreSQL 9.0 has been changed to output bytea in hex encoding. ST_AsBinary is the reverse of for geometry. If your GUI tools require the old behavior, then SET bytea_output='escape' in your database. Enhanced: 2.0.0 support for Polyhedral surfaces, Triangles and TIN was introduced. Availability: 1.5.0 geography support was introduced. &sfs_compliant; s2.1.1.1 &sqlmm_compliant; SQL-MM 3: 5.1.37 &curve_support; &P_support; &T_support; SELECT ST_AsBinary(ST_GeomFromText('POLYGON((0 0,0 1,1 1,1 0,0 0))',4326)); st_asbinary -------------------------------- \001\003\000\000\000\001\000\000\000\005 \000\000\000\000\000\000\000\000\000\000 \000\000\000\000\000\000\000\000\000\000 \000\000\000\000\000\000\000\000\000\000 \000\000\000\360?\000\000\000\000\000\000 \360?\000\000\000\000\000\000\360?\000\000 \000\000\000\000\360?\000\000\000\000\000 \000\000\000\000\000\000\000\000\000\000\000 \000\000\000\000\000\000\000\000 (1 row) SELECT ST_AsBinary(ST_GeomFromText('POLYGON((0 0,0 1,1 1,1 0,0 0))',4326), 'XDR'); st_asbinary -------------------------------- \000\000\000\000\003\000\000\000\001\000\000\000\005\000\000\000\000\000 \000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000 \000?\360\000\000\000\000\000\000?\360\000\000\000\000\000\000?\360\000\000 \000\000\000\000?\360\000\000\000\000\000\000\000\000\000\000\000\000\000\000 \000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000 (1 row) , , , ST_AsEWKB Return the Well-Known Binary (WKB) representation of the geometry with SRID meta data. bytea ST_AsEWKB geometry g1 bytea ST_AsEWKB geometry g1 text NDR_or_XDR Returns the Well-Known Binary representation of the geometry with SRID metadata. There are 2 variants of the function. The first variant takes no endian encoding parameter and defaults to little endian. The second variant takes a second argument denoting the encoding - using little-endian ('NDR') or big-endian ('XDR') encoding. This is useful in binary cursors to pull data out of the database without converting it to a string representation. The WKB spec does not include the SRID. To get the OGC WKB format use ST_AsBinary ST_AsEWKB is the reverse of ST_GeomFromEWKB. Use ST_GeomFromEWKB to convert to a postgis geometry from ST_AsEWKB representation. Enhanced: 2.0.0 support for Polyhedral surfaces, Triangles and TIN was introduced. &Z_support; &curve_support; &P_support; &T_support; SELECT ST_AsEWKB(ST_GeomFromText('POLYGON((0 0,0 1,1 1,1 0,0 0))',4326)); st_asewkb -------------------------------- \001\003\000\000 \346\020\000\000\001\000 \000\000\005\000\000\000\000 \000\000\000\000\000\000\000\000 \000\000\000\000\000\000\000\000\000 \000\000\000\000\000\000\000\000\000\000 \000\000\360?\000\000\000\000\000\000\360? \000\000\000\000\000\000\360?\000\000\000\000\000 \000\360?\000\000\000\000\000\000\000\000\000\000\000 \000\000\000\000\000\000\000\000\000\000\000\000\000 (1 row) SELECT ST_AsEWKB(ST_GeomFromText('POLYGON((0 0,0 1,1 1,1 0,0 0))',4326), 'XDR'); st_asewkb -------------------------------- \000 \000\000\003\000\000\020\346\000\000\000\001\000\000\000\005\000\000\000\000\ 000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000? \360\000\000\000\000\000\000?\360\000\000\000\000\000\000?\360\000\000\000\000 \000\000?\360\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000\000 \000\000\000\000\000\000\000\000\000\000\000\000\000 , , , , ST_AsEWKT Return the Well-Known Text (WKT) representation of the geometry with SRID meta data. text ST_AsEWKT geometry g1 Returns the Well-Known Text representation of the geometry prefixed with the SRID. The WKT spec does not include the SRID. To get the OGC WKT format use ST_AsText WKT format does not maintain precision so to prevent floating truncation, use ST_AsBinary or ST_AsEWKB format for transport. ST_AsEWKT is the reverse of . Use to convert to a postgis geometry from ST_AsEWKT representation. Enhanced: 2.0.0 support for Polyhedral surfaces, Triangles and TIN was introduced. &Z_support; &curve_support; &P_support; &T_support; SELECT ST_AsEWKT('0103000020E61000000100000005000000000000 000000000000000000000000000000000000000000000000000000 F03F000000000000F03F000000000000F03F000000000000F03 F000000000000000000000000000000000000000000000000'::geometry); st_asewkt -------------------------------- SRID=4326;POLYGON((0 0,0 1,1 1,1 0,0 0)) (1 row) SELECT ST_AsEWKT('0108000080030000000000000060E30A4100000000785C0241000000000000F03F0000000018 E20A4100000000485F024100000000000000400000000018 E20A4100000000305C02410000000000000840') --st_asewkt--- CIRCULARSTRING(220268 150415 1,220227 150505 2,220227 150406 3) , ST_AsGeoJSON Return the geometry as a GeoJSON element. text ST_AsGeoJSON geometry g1 text ST_AsGeoJSON geography g1 text ST_AsGeoJSON geometry g1 integer max_decimal_digits text ST_AsGeoJSON geography g1 integer max_decimal_digits text ST_AsGeoJSON geometry g1 integer max_decimal_digits integer options text ST_AsGeoJSON geography g1 integer max_decimal_digits integer options text ST_AsGeoJSON integer version geometry g1 text ST_AsGeoJSON integer gj_version geography g1 text ST_AsGeoJSON integer gj_version geometry g1 integer max_decimal_digits text ST_AsGeoJSON integer gj_version geography g1 integer max_decimal_digits text ST_AsGeoJSON integer gj_version geometry g1 integer max_decimal_digits integer options text ST_AsGeoJSON integer gj_version geography g1 integer max_decimal_digits integer options Return the geometry as a Geometry Javascript Object Notation (GeoJSON) element. (Cf GeoJSON specifications 1.0). 2D and 3D Geometries are both supported. GeoJSON only support SFS 1.1 geometry type (no curve support for example). The gj_version parameter is the major version of the GeoJSON spec. If specified, must be 1. This represents the spec version of GeoJSON. The third argument may be used to reduce the maximum number of decimal places used in output (defaults to 15). The last 'options' argument could be used to add Bbox or Crs in GeoJSON output: 0: means no option (default value) 1: GeoJSON Bbox 2: GeoJSON Short CRS (e.g EPSG:4326) 4: GeoJSON Long CRS (e.g urn:ogc:def:crs:EPSG::4326) Version 1: ST_AsGeoJSON(geom) / precision=15 version=1 options=0 Version 2: ST_AsGeoJSON(geom, precision) / version=1 options=0 Version 3: ST_AsGeoJSON(geom, precision, options) / version=1 Version 4: ST_AsGeoJSON(gj_version, geom) / precision=15 options=0 Version 5: ST_AsGeoJSON(gj_version, geom, precision) /options=0 Version 6: ST_AsGeoJSON(gj_version, geom, precision,options) Availability: 1.3.4 Availability: 1.5.0 geography support was introduced. &Z_support; GeoJSON format is generally more efficient than other formats for use in ajax mapping. One popular javascript client that supports this is Open Layers. Example of its use is OpenLayers GeoJSON Example SELECT ST_AsGeoJSON(the_geom) from fe_edges limit 1; st_asgeojson ----------------------------------------------------------------------------------------------------------- {"type":"MultiLineString","coordinates":[[[-89.734634999999997,31.492072000000000], [-89.734955999999997,31.492237999999997]]]} (1 row) --3d point SELECT ST_AsGeoJSON('LINESTRING(1 2 3, 4 5 6)'); st_asgeojson ----------------------------------------------------------------------------------------- {"type":"LineString","coordinates":[[1,2,3],[4,5,6]]} ST_AsGML Return the geometry as a GML version 2 or 3 element. text ST_AsGML geometry geom integer maxdecimaldigits=15 integer options=0 text ST_AsGML geography geog integer maxdecimaldigits=15 integer options=0 text ST_AsGML integer version geometry g1 integer maxdecimaldigits=15 integer options=0 text nprefix=null text ST_AsGML integer version geography geog integer maxdecimaldigits=15 integer options=0 text nprefix=null Return the geometry as a Geography Markup Language (GML) element. The version parameter, if specified, may be either 2 or 3. If no version parameter is specified then the default is assumed to be 2. The precision argument may be used to reduce the maximum number of decimal places (maxdecimaldigits) used in output (defaults to 15). GML 2 refer to 2.1.2 version, GML 3 to 3.1.1 version The 'options' argument is a bitfield. It could be used to define CRS output type in GML output, and to declare data as lat/lon: 0: GML Short CRS (e.g EPSG:4326), default value 1: GML Long CRS (e.g urn:ogc:def:crs:EPSG::4326) 2: For GML 3 only, remove srsDimension attribute from output. 4: For GML 3 only, use <LineString> rather than <Curve> tag for lines. 16: Declare that datas are lat/lon (e.g srid=4326). Default is to assume that data are planars. This option is useful for GML 3.1.1 output only, related to axis order. So if you set it, it will swap the coordinates so order is lat lon instead of database lon lat. 32: Output the box of the geometry (envelope). The 'namespace prefix' argument may be used to specify a custom namespace prefix or no prefix (if empty). If null or omitted 'gml' prefix is used Availability: 1.3.2 Availability: 1.5.0 geography support was introduced. Enhanced: 2.0.0 prefix support was introduced. Option 4 for GML3 was introduced to allow using LineString instead of Curve tag for lines. GML3 Support for Polyhedral surfaces and TINS was introduced. Option 32 was introduced to output the box. Changed: 2.0.0 use default named args Only version 3+ of ST_AsGML supports Polyhedral Surfaces and TINS. &Z_support; &P_support; &T_support; 0,0 0,1 1,1 1,0 0,0]]> -- Flip coordinates and output extended EPSG (16 | 1)-- 6.34535 5.23423]]> -- Output the envelope (32) -- 1 2 10 20 ]]> -- Output the envelope (32) , reverse (lat lon instead of lon lat) (16), long srs (1)= 32 | 16 | 1 = 49 -- 2 1 20 10 ]]> -- Polyhedral Example -- SELECT ST_AsGML(3, ST_GeomFromEWKT('POLYHEDRALSURFACE( ((0 0 0, 0 0 1, 0 1 1, 0 1 0, 0 0 0)), ((0 0 0, 0 1 0, 1 1 0, 1 0 0, 0 0 0)), ((0 0 0, 1 0 0, 1 0 1, 0 0 1, 0 0 0)), ((1 1 0, 1 1 1, 1 0 1, 1 0 0, 1 1 0)), ((0 1 0, 0 1 1, 1 1 1, 1 1 0, 0 1 0)), ((0 0 1, 1 0 1, 1 1 1, 0 1 1, 0 0 1)) )')); st_asgml -------- 0 0 0 0 0 1 0 1 1 0 1 0 0 0 0 0 0 0 0 1 0 1 1 0 1 0 0 0 0 0 0 0 0 1 0 0 1 0 1 0 0 1 0 0 0 1 1 0 1 1 1 1 0 1 1 0 0 1 1 0 0 1 0 0 1 1 1 1 1 1 1 0 0 1 0 0 0 1 1 0 1 1 1 1 0 1 1 0 0 1 ]]> ST_AsHEXEWKB Returns a Geometry in HEXEWKB format (as text) using either little-endian (NDR) or big-endian (XDR) encoding. text ST_AsHEXEWKB geometry g1 text NDRorXDR text ST_AsHEXEWKB geometry g1 Returns a Geometry in HEXEWKB format (as text) using either little-endian (NDR) or big-endian (XDR) encoding. If no encoding is specified, then NDR is used. Availability: 1.2.2 &Z_support; &curve_support; SELECT ST_AsHEXEWKB(ST_GeomFromText('POLYGON((0 0,0 1,1 1,1 0,0 0))',4326)); which gives same answer as SELECT ST_GeomFromText('POLYGON((0 0,0 1,1 1,1 0,0 0))',4326)::text; st_ashexewkb -------- 0103000020E6100000010000000500 00000000000000000000000000000000 00000000000000000000000000000000F03F 000000000000F03F000000000000F03F000000000000F03 F000000000000000000000000000000000000000000000000 ST_AsKML Return the geometry as a KML element. Several variants. Default version=2, default precision=15 text ST_AsKML geometry g1 text ST_AsKML geography g1 text ST_AsKML geometry g1 integer precision text ST_AsKML geography g1 integer precision text ST_AsKML integer version geometry geom1 text ST_AsKML integer version geography geom1 text ST_AsKML integer version geometry geom1 integer precision text ST_AsKML integer version geography geom1 integer precision text ST_AsKML integer version geometry geom1 integer precision text namespace prefix text ST_AsKML integer version geography geog1 integer precision text namespace prefix Return the geometry as a Keyhole Markup Language (KML) element. There are several variants of this function. maximum number of decimal places used in output (defaults to 15), version default to 2 and default namespace is no prefix. Version 1: ST_AsKML(geom) / version=2 precision=15 Version 2: ST_AsKML(geom, max_sig_digits) / version=2 Version 3: ST_AsKML(version, geom) / precision=15 Version 4: ST_AsKML(version, geom, precision) Version 5: ST_AsKML(version, geom, precision, namespace_prefix) Requires PostGIS be compiled with Proj support. Use to confirm you have proj support compiled in. Availability: 1.2.2 - later variants that include version param came in 1.3.2 Enhanced: 2.0.0 - Add prefix namespace. Default is no prefix AsKML output will not work with geometries that do not have an SRID &Z_support; 0,0 0,1 1,1 1,0 0,0 --3d linestring SELECT ST_AsKML('SRID=4326;LINESTRING(1 2 3, 4 5 6)'); 1,2,3 4,5,6 ]]> , ST_AsSVG Returns a Geometry in SVG path data given a geometry or geography object. text ST_AsSVG geometry geom integer rel=0 integer maxdecimaldigits=15 text ST_AsSVG geography geog integer rel=0 integer maxdecimaldigits=15 Return the geometry as Scalar Vector Graphics (SVG) path data. Use 1 as second argument to have the path data implemented in terms of relative moves, the default (or 0) uses absolute moves. Third argument may be used to reduce the maximum number of decimal digits used in output (defaults to 15). Point geometries will be rendered as cx/cy when 'rel' arg is 0, x/y when 'rel' is 1. Multipoint geometries are delimited by commas (","), GeometryCollection geometries are delimited by semicolons (";"). Availability: 1.2.2. Availability: 1.4.0 Changed in PostGIS 1.4.0 to include L command in absolute path to conform to http://www.w3.org/TR/SVG/paths.html#PathDataBNF Changed: 2.0.0 to use default args and support named args SELECT ST_AsSVG(ST_GeomFromText('POLYGON((0 0,0 1,1 1,1 0,0 0))',4326)); st_assvg -------- M 0 0 L 0 -1 1 -1 1 0 Z ST_AsX3D Returns a Geometry in X3D xml node element format: ISO-IEC-19776-1.2-X3DEncodings-XML text ST_AsX3D geometry g1 integer prec=15 integer options=0 Returns a geometry as an X3D xml formatted node element http://web3d.org/x3d/specifications/ISO-IEC-19776-1.2-X3DEncodings-XML/Part01/EncodingOfNodes.html. If prec (precision) is not specified then defaults to 15. There are various options for translating PostGIS geometries to X3D since X3D geometry types don't map directly to PostGIS geometry types and some newer X3D types that might be better mappings we ahve avoided since most rendering tools don't currently support them. These are the mappings we have settled on. Feel free to post a bug ticket if you have thoughts on the idea or ways we can allow people to denote their preferred mappings. Below is how we currently map PostGIS 2D/3D types to X3D types PostGIS Type 2D X3D Type 3D X3D Type LINESTRING not yet implemented - will be PolyLine2D LineSet MULTILINESTRING not yet implemented - will be PolyLine2D IndexedLineSet MULTIPOINT Polypoint2D PointSet POINT outputs the space delimited coordinates outputs the space delimited coordinates (MULTI) POLYGON, POLYHEDRALSURFACE Invalid X3D markup IndexedFaceSet (inner rings currently output as another faceset) TIN TriangleSet2D (Not Yet Implemented) IndexedTriangleSet 2D geometry support not yet complete. Inner rings currently just drawn as separate polygons. We are working on these. Lots of advancements happening in 3D space particularly with X3D Integration with HTML5 There is also a nice open source X3D viewer you can use to view rendered geometries. Free Wrl http://freewrl.sourceforge.net/ binaries available for Mac, Linux, and Windows. Use the FreeWRL_Launcher packaged to view the geometries. Availability: 2.0.0: ISO-IEC-19776-1.2-X3DEncodings-XML &Z_support; &P_support; &T_support; ' || ST_AsX3D( ST_GeomFromEWKT('POLYHEDRALSURFACE( ((0 0 0, 0 0 1, 0 1 1, 0 1 0, 0 0 0)), ((0 0 0, 0 1 0, 1 1 0, 1 0 0, 0 0 0)), ((0 0 0, 1 0 0, 1 0 1, 0 0 1, 0 0 0)), ((1 1 0, 1 1 1, 1 0 1, 1 0 0, 1 1 0)), ((0 1 0, 0 1 1, 1 1 1, 1 1 0, 0 1 0)), ((0 0 1, 1 0 1, 1 1 1, 0 1 1, 0 0 1)) )')) || ' ' As x3ddoc;]]> x3ddoc -------- ]]> SELECT ST_AsX3D( ST_Translate( ST_Force_3d( ST_Buffer(ST_Point(10,10),5, 'quad_segs=2')), 0,0, 3) ,6) As x3dfrag; x3dfrag -------- ]]> x3dfrag -------- ]]> x3dfrag -------- ]]> ST_GeoHash Return a GeoHash representation (geohash.org) of the geometry. text ST_GeoHash geometry g1 text ST_GeoHash geometry g1 integer precision Return a GeoHash representation (geohash.org) of the geometry. A GeoHash encodes a point into a text form that is sortable and searchable based on prefixing. A shorter GeoHash is a less precise representation of a point. It can also be thought of as a box, that contains the actual point. The one-parameter variant of ST_GeoHash returns a GeoHash based on the input geometry type. Points return a GeoHash with 20 characters of precision (about enough to hold the full double precision of the input). Other types return a GeoHash with a variable amount of precision, based on the size of the feature. Larger features are represented with less precision, smaller features with more precision. The idea is that the box implied by the GeoHash will always contain the input feature. The two-parameter variant of ST_GeoHash returns a GeoHash with a requested precision. For non-points, the starting point of the calculation is the center of the bounding box of the geometry. Availability: 1.4.0 ST_GeoHash will not work with geometries that are not in geographic (lon/lat) coordinates. &curve_support; ST_AsText Return the Well-Known Text (WKT) representation of the geometry/geography without SRID metadata. text ST_AsText geometry g1 text ST_AsText geography g1 Returns the Well-Known Text representation of the geometry/geography. The WKT spec does not include the SRID. To get the SRID as part of the data, use the non-standard PostGIS WKT format does not maintain precision so to prevent floating truncation, use ST_AsBinary or ST_AsEWKB format for transport. ST_AsText is the reverse of . Use to convert to a postgis geometry from ST_AsText representation. Availability: 1.5 - support for geography was introduced. &sfs_compliant; s2.1.1.1 &sqlmm_compliant; SQL-MM 3: 5.1.25 &curve_support; SELECT ST_AsText('01030000000100000005000000000000000000 000000000000000000000000000000000000000000000000 F03F000000000000F03F000000000000F03F000000000000F03 F000000000000000000000000000000000000000000000000'); st_astext -------------------------------- POLYGON((0 0,0 1,1 1,1 0,0 0)) (1 row) , , , ST_AsLatLonText Return the Degrees, Minutes, Seconds representation of the given point. text ST_AsLatLonText geometry pt text ST_AsLatLonText geometry pt text format Returns the Degrees, Minutes, Seconds representation of the point. It is assumed the point is in a lat/lon projection. The X (lon) and Y (lat) coordinates are normalized in the output to the "normal" range (-180 to +180 for lon, -90 to +90 for lat). The text parameter is a format string containing the format for the resulting text, similar to a date format string. Valid tokens are "D" for degrees, "M" for minutes, "S" for seconds, and "C" for cardinal direction (NSEW). DMS tokens may be repeated to indicate desired width and precision ("SSS.SSSS" means " 1.0023"). "M", "S", and "C" are optional. If "C" is omitted, degrees are shown with a "-" sign if south or west. If "S" is omitted, minutes will be shown as decimal with as many digits of precision as you specify. If "M" is also omitted, degrees are shown as decimal with as many digits precision as you specify. If the format string is omitted (or zero-length) a default format will be used. Availability: 2.0 Default format. SELECT (ST_AsLatLonText('POINT (-3.2342342 -2.32498)')); st_aslatlontext ---------------------------- 2°19'29.928"S 3°14'3.243"W Providing a format (same as the default). SELECT (ST_AsLatLonText('POINT (-3.2342342 -2.32498)', 'D°M''S.SSS"C')); st_aslatlontext ---------------------------- 2°19'29.928"S 3°14'3.243"W Characters other than D, M, S, C and . are just passed through. SELECT (ST_AsLatLonText('POINT (-3.2342342 -2.32498)', 'D degrees, M minutes, S seconds to the C')); st_aslatlontext -------------------------------------------------------------------------------------- 2 degrees, 19 minutes, 30 seconds to the S 3 degrees, 14 minutes, 3 seconds to the W Signed degrees instead of cardinal directions. SELECT (ST_AsLatLonText('POINT (-3.2342342 -2.32498)', 'D°M''S.SSS"')); st_aslatlontext ---------------------------- -2°19'29.928" -3°14'3.243" Decimal degrees. SELECT (ST_AsLatLonText('POINT (-3.2342342 -2.32498)', 'D.DDDD degrees C')); st_aslatlontext ----------------------------------- 2.3250 degrees S 3.2342 degrees W Excessively large values are normalized. SELECT (ST_AsLatLonText('POINT (-302.2342342 -792.32498)')); st_aslatlontext ------------------------------- 72°19'29.928"S 57°45'56.757"E