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18.4.2.1. Creating Geometry Values Using WKT Functions
MySQL provides a number of functions that take as input
parameters a Well-Known Text representation and, optionally, a
spatial reference system identifier (SRID). They return the
corresponding geometry.
GeomFromText() accepts a WKT of any
geometry type as its first argument. An implementation also
provides type-specific construction functions for construction
of geometry values of each geometry type.
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GeomCollFromText(wkt[,srid]),
GeometryCollectionFromText(wkt[,srid])
Constructs a GEOMETRYCOLLECTION value
using its WKT representation and SRID.
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GeomFromText(wkt[,srid]),
GeometryFromText(wkt[,srid])
Constructs a geometry value of any type using its WKT
representation and SRID.
-
LineFromText(wkt[,srid]),
LineStringFromText(wkt[,srid])
Constructs a LINESTRING value using its
WKT representation and SRID.
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MLineFromText(wkt[,srid]),
MultiLineStringFromText(wkt[,srid])
Constructs a MULTILINESTRING value
using its WKT representation and SRID.
-
MPointFromText(wkt[,srid]),
MultiPointFromText(wkt[,srid])
Constructs a MULTIPOINT value using its
WKT representation and SRID.
-
MPolyFromText(wkt[,srid]),
MultiPolygonFromText(wkt[,srid])
Constructs a MULTIPOLYGON value using
its WKT representation and SRID.
-
PointFromText(wkt[,srid])
Constructs a POINT value using its WKT
representation and SRID.
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PolyFromText(wkt[,srid]),
PolygonFromText(wkt[,srid])
Constructs a POLYGON value using its
WKT representation and SRID.
The OpenGIS specification also defines the following optional
functions, which MySQL does not implement. These functions
construct Polygon or
MultiPolygon values based on the WKT
representation of a collection of rings or closed
LineString values. These values may
intersect.
-
BdMPolyFromText(wkt,srid)
Constructs a MultiPolygon value from a
MultiLineString value in WKT format
containing an arbitrary collection of closed
LineString values.
-
BdPolyFromText(wkt,srid)
Constructs a Polygon value from a
MultiLineString value in WKT format
containing an arbitrary collection of closed
LineString values.
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