MySQL 9.3 Reference Manual Including MySQL NDB Cluster 9.3
MySQL provides a set of useful nonstandard functions for creating geometry values. The functions described in this section are MySQL extensions to the OpenGIS specification.
These functions produce geometry objects from either WKB values or
geometry objects as arguments. If any argument is not a proper WKB
or geometry representation of the proper object type, the return
value is NULL
.
For example, you can insert the geometry return value from
Point()
directly into a
POINT
column:
INSERT INTO t1 (pt_col) VALUES(Point(1,2));
Constructs a GeomCollection
value from the
geometry arguments.
GeomCollection()
returns all
the proper geometries contained in the arguments even if a
nonsupported geometry is present.
GeomCollection()
with no
arguments is permitted as a way to create an empty geometry.
Also, functions such as
ST_GeomFromText()
that accept
WKT geometry collection arguments understand both OpenGIS
'GEOMETRYCOLLECTION EMPTY'
standard syntax
and MySQL 'GEOMETRYCOLLECTION()'
nonstandard syntax.
GeomCollection()
and
GeometryCollection()
are
synonymous, with
GeomCollection()
the preferred
function.
GeometryCollection(
g
[, g
] ...)
Constructs a GeomCollection
value from the
geometry arguments.
GeometryCollection()
returns
all the proper geometries contained in the arguments even if a
nonsupported geometry is present.
GeometryCollection()
with no
arguments is permitted as a way to create an empty geometry.
Also, functions such as
ST_GeomFromText()
that accept
WKT geometry collection arguments understand both OpenGIS
'GEOMETRYCOLLECTION EMPTY'
standard syntax
and MySQL 'GEOMETRYCOLLECTION()'
nonstandard syntax.
GeomCollection()
and
GeometryCollection()
are
synonymous, with
GeomCollection()
the preferred
function.
Constructs a LineString
value from a number
of Point
or WKB Point
arguments. If the number of arguments is less than two, the
return value is NULL
.
MultiLineString(
ls
[, ls
] ...)
Constructs a MultiLineString
value using
LineString
or WKB
LineString
arguments.
Constructs a MultiPoint
value using
Point
or WKB Point
arguments.
MultiPolygon(
poly
[, poly
] ...)
Constructs a MultiPolygon
value from a set
of Polygon
or WKB
Polygon
arguments.
Constructs a Point
using its coordinates.
Constructs a Polygon
value from a number of
LineString
or WKB
LineString
arguments. If any argument does
not represent a LinearRing
(that is, not a
closed and simple LineString
), the return
value is NULL
.