- A &< B
-
The "&<" operator returns true if A's bounding
box overlaps or is to the left of B's bounding box.
- A &> B
-
The "&>" operator returns true if A's bounding
box overlaps or is to the right of B's bounding box.
- A << B
-
The "<<" operator returns true if A's bounding
box is strictly to the left of B's bounding box.
- A >> B
-
The ">>" operator returns true if A's bounding
box is strictly to the right of B's bounding box.
- A ~= B
-
The "~=" operator is the "same as" operator. It tests
actual geometric equality of two features. So if A and B are the
same feature, vertex-by-vertex, the operator returns true.
- A @ B
-
The "@" operator returns true if A's bounding box
is completely contained by B's bounding box.
- A ~ B
-
The "~" operator returns true if A's bounding box
completely contains B's bounding box.
- A && B
-
The "&&" operator is the "overlaps" operator.
If A's bounding boux overlaps B's bounding box the operator returns
true.
- area2d(geometry)
-
Returns the area of the geometry if it is a polygon
or multi-polygon.
- area(geometry)
-
Returns the area of the geometry if it is a polygon
or multi-polygon. (same as area2(<polygon|multipolygon>)
- asbinary(geometry,'NDR')
-
Returns the geometry in the OGC "well-known-binary"
format, using little-endian encoding. This is useful in binary cursors
to pull data out of the database without converting it to a string
representation.
- isvalid(geometry)
-
returns true if this geometry is valid.
- asbinary(geometry,'XDR')
-
Returns the geometry in the OGC "well-known-binary"
format, using big-endian encoding. This is useful in binary cursors
to pull data out of the database without converting it to a string
representation.
- GeomFromText(text,[<srid>])
-
Makes a Geometry from WKT with the given SRID. If
SRID is not give, it defaults to -1.
OGC SPEC 3.2.6.2 - option SRID is from the conformance
suite
- GeometryFromText(text,[<srid>])
-
Makes a Geometry from WKT with the given SRID. If
SRID is not give, it defaults to -1.
OGC SPEC 3.2.6.2 - option SRID is from the conformance
suite
- PointFromText(text,[<srid>])
-
Makes a Geometry from WKT with the given SRID. If
SRID is not give, it defaults to -1.
OGC SPEC 3.2.6.2 - option SRID is from the conformance
suite
Throws an error if the WKT is not a Point
- LineFromText(text,[<srid>])
-
Makes a Geometry from WKT with the given SRID. If
SRID is not give, it defaults to -1.
OGC SPEC 3.2.6.2 - option SRID is from the conformance
suite
Throws an error if the WKT is not a Line
- LinestringFromText(text,[<srid>])
-
Makes a Geometry from WKT with the given SRID. If
SRID is not give, it defaults to -1.
from the conformance suite
Throws an error if the WKT is not a Line
- PolyFromText(text,[<srid>])
-
Makes a Geometry from WKT with the given SRID. If
SRID is not give, it defaults to -1.
OGC SPEC 3.2.6.2 - option SRID is from the conformance
suite
Throws an error if the WKT is not a Polygon
- PolygonFromText(text,[<srid>])
-
Makes a Geometry from WKT with the given SRID. If
SRID is not give, it defaults to -1.
from the conformance suite
Throws an error if the WKT is not a Polygon
- MPointFromText(text,[<srid>])
-
Makes a Geometry from WKT with the given SRID. If
SRID is not give, it defaults to -1.
OGC SPEC 3.2.6.2 - option SRID is from the conformance
suite
Throws an error if the WKT is not a MULTIPOINT
- MLineFromText(text,[<srid>])
-
Makes a Geometry from WKT with the given SRID. If
SRID is not give, it defaults to -1.
OGC SPEC 3.2.6.2 - option SRID is from the conformance
suite
Throws an error if the WKT is not a MULTILINESTRING
- MPolyFromText(text,[<srid>])
-
Makes a Geometry from WKT with the given SRID. If
SRID is not give, it defaults to -1.
OGC SPEC 3.2.6.2 - option SRID is from the conformance
suite
Throws an error if the WKT is not a MULTIPOLYGON
- GeomCollFromText(text,[<srid>])
-
Makes a Geometry from WKT with the given SRID. If
SRID is not give, it defaults to -1.
OGC SPEC 3.2.6.2 - option SRID is from the conformance
suite
Throws an error if the WKT is not a GEOMETRYCOLLECTION
- GeomFromWKB(text,[<srid>])
-
Makes a Geometry from WKB with the given SRID. If
SRID is not give, it defaults to -1.
OGC SPEC 3.2.6.2 - option SRID is from the conformance
suite
- GeometryFromWKB(text,[<srid>])
-
Makes a Geometry from WKB with the given SRID. If
SRID is not give, it defaults to -1.
OGC SPEC 3.2.6.2 - option SRID is from the conformance
suite
- PointFromWKB(text,[<srid>])
-
Makes a Geometry from WKB with the given SRID. If
SRID is not give, it defaults to -1.
OGC SPEC 3.2.6.2 - option SRID is from the conformance
suite
throws an error if WKB is not a POINT
- LineFromWKB(text,[<srid>])
-
Makes a Geometry from WKB with the given SRID. If
SRID is not give, it defaults to -1.
OGC SPEC 3.2.6.2 - option SRID is from the conformance
suite
throws an error if WKB is not a LINESTRING
- LinestringFromWKB(text,[<srid>])
-
Makes a Geometry from WKB with the given SRID. If
SRID is not give, it defaults to -1.
from the conformance suite
throws an error if WKB is not a LINESTRING
- PolyFromWKB(text,[<srid>])
-
Makes a Geometry from WKB with the given SRID. If
SRID is not give, it defaults to -1.
OGC SPEC 3.2.6.2 - option SRID is from the conformance
suite
throws an error if WKB is not a POLYGON
- PolygonFromWKB(text,[<srid>])
-
Makes a Geometry from WKB with the given SRID. If
SRID is not give, it defaults to -1.
from the conformance suite
throws an error if WKB is not a POLYGON
- MPointFromWKB(text,[<srid>])
-
Makes a Geometry from WKB with the given SRID. If
SRID is not give, it defaults to -1.
OGC SPEC 3.2.6.2 - option SRID is from the conformance
suite
throws an error if WKB is not a MULTIPOINT
- MLineFromWKB(text,[<srid>])
-
Makes a Geometry from WKB with the given SRID. If
SRID is not give, it defaults to -1.
OGC SPEC 3.2.6.2 - option SRID is from the conformance
suite
throws an error if WKB is not a MULTILINESTRING
- MPolyFromWKB(text,[<srid>])
-
Makes a Geometry from WKB with the given SRID. If
SRID is not give, it defaults to -1.
OGC SPEC 3.2.6.2 - option SRID is from the conformance
suite
throws an error if WKB is not a MULTIPOLYGON
- GeomCollFromWKB(text,[<srid>])
-
Makes a Geometry from WKB with the given SRID. If
SRID is not give, it defaults to -1.
OGC SPEC 3.2.6.2 - option SRID is from the conformance
suite
throws an error if WKB is not a GEOMETRYCOLLECTION
- PointOnSurface(geometry)
-
Return a Point guaranteed to lie on the surface
Implemented using GEOS
OGC SPEC 3.2.14.2 and 3.2.18.2 -
- box3d(geometry)
-
Returns a BOX3D representing the maximum extents
of the geometry.
- collect(geometry set)
-
This function returns a GEOMETRYCOLLECTION object
from a set of geometries. The collect() function is an "aggregate"
function in the terminology of PostgreSQL. That means that it operators
on lists of data, in the same way the sum() and mean() functions
do. For example, "SELECT COLLECT(GEOM) FROM GEOMTABLE GROUP BY ATTRCOLUMN"
will return a separate GEOMETRYCOLLECTION for each distinct value
of ATTRCOLUMN.
- mem_collect(geometry set)
-
This does the the same of collect(geometry), only
more memory-friendly (uses less memory and more processor time).
- distance_spheroid(point, point, spheroid)
-
Returns linear distance between two lat/lon points
given a particular spheroid. See the explanation of spheroids given
for length_spheroid(). Currently only implemented for points.
- extent(geometry set)
-
The extent() function is an "aggregate" function
in the terminology of PostgreSQL. That means that it operators on
lists of data, in the same way the sum() and mean() functions do.
For example, "SELECT EXTENT(GEOM) FROM GEOMTABLE" will return a BOX3D
giving the maximum extend of all features in the table. Similarly,
"SELECT EXTENT(GEOM) FROM GEOMTABLE GROUP BY CATEGORY" will return
one extent result for each category.
- find_srid(varchar,varchar,varchar)
-
The syntax is find_srid(<db/schema>, <table>,
<column>) and the function returns the integer SRID of the specified
column by searching through the GEOMETRY_COLUMNS table. If the geometry column
has not been properly added with the AddGeometryColumns() function, this
function will not work either.
- force_collection(geometry)
-
Converts the geometry into a GEOMETRYCOLLECTION.
This is useful for simplifying the WKB representation.
- force_2d(geometry)
-
Forces the geometries into a "2-dimensional mode"
so that all output representations will only have the X and Y coordinates.
This is useful for force OGC-compliant output (since OGC only specifies
2-D geometries).
- force_3d(geometry)
-
Forces the geometries into a "3-dimensional mode"
so that all output representations will have the X, Y and Z coordinates.
- length2d(geometry)
-
Returns the 2-dimensional length of the geometry
if it is a linestring or multi-linestring.
- length(geometry)
-
The length of this Curve in its associated spatial
reference.
synonym for length2d()
OGC SPEC 2.1.5.1
- length3d(geometry)
-
Returns the 3-dimensional length of the geometry
if it is a linestring or multi-linestring.
- length_spheroid(geometry,spheroid)
-
Calculates the length of of a geometry on
an elipsoid. This is useful if the coordinates of the geometry are
in latitude/longitude and a length is desired without reprojection.
The elipsoid is a separate database type and can be constructed as
follows:
SPHEROID[<NAME>,<SEMI-MAJORšAXIS>,<INVERSEšFLATTENING>]
Eg:
SPHEROID["GRS_1980",6378137,298.257222101]
An example calculation might look like this:
SELECT
length_spheroid(
geometry_column,
'SPHEROID["GRS_1980",6378137,298.257222101]'
)
FROMšgeometry_table;
- length3d_spheroid(geometry,spheroid)
-
Calculates the length of of a geometry on
an elipsoid, taking the elevation into account. This is just like
length_spheroid except vertical coordinates (expressed in the same
units as the spheroid axes) are used to calculate the extra distance
vertical displacement adds.
- max_distance(linestring,linestring)
-
Returns the largest distance between two
line strings.
- mem_size(geometry)
-
Returns the amount of space (in bytes) the
geometry takes.
- npoints(geometry)
-
Returns the number of points in the geometry.
- nrings(geometry)
-
If the geometry is a polygon or multi-polygon
returns the number of rings.
- numb_sub_objects(geometry)
-
Returns the number of objects stored in
the geometry. This is useful for MULTI-geometries and GEOMETRYCOLLECTIONs.
- perimeter2d(geometry)
-
Returns the 2-dimensional perimeter of the
geometry, if it is a polygon or multi-polygon.
- perimeter3d(geometry)
-
Returns the 3-dimensional perimeter of the
geometry, if it is a polygon or multi-polygon.
- point_inside_circle(geometry,float,float,float)
-
The syntax for this functions is
point_inside_circle(<geometry>,<circle_center_x>,<circle_center_y>,<radius>).
Returns the true if the geometry is a point and is inside the circle.
Returns false otherwise.
- postgis_version()
-
Returns the version number of the PostGIS
functions installed in this database.
- summary(geometry)
-
Returns a text summary of the contents of
the geometry.
- transform(geometry,integer)
-
Returns a new geometry with its coordinates
transformed to the SRID referenced by the integer parameter. The destination
SRID must exist in the SPATIAL_REF_SYS table.
- translate(geometry,float8,float8,float8)
-
Translates the geometry to a new location
using the numeric parameters as offsets. Ie: translate(geom,X,Y,Z).
- xmin(box3d) ymin(box3d) zmin(box3d)
-
Returns the requested minima of a bounding
box.
- xmax(box3d) ymax(box3d) zmax(box3d)
-
Returns the requested maxima of a bounding
box.
- simplify(geometry, tolerance)
-
Returns a "simplified" version of the given
geometry using the Douglas-Peuker algorithm. Will actually do something only
with (multi)lines and (multi)polygons but you can safely call it with any
kind of geometry. Since simplification occurs on a object-by-object basis
you can also feed a GeometryCollection to this function. Note that returned
geometry might loose its simplicity (see isSimple)