11.4.2.3 Creating Geometry Values Using MySQL-Specific Functions

Note: MySQL does not yet implement the functions listed in this section.

MySQL provides a set of useful functions for creating geometry WKB representations. The functions described in this section are MySQL extensions to the OpenGIS specifications. The results of these functions are BLOB values containing WKB representations of geometry values with no SRID. The results of these functions can be substituted as the first argument for any function in the GeomFromWKB() function family.

Point(x,y)

Constructs a WKB Point using its coordinates.

MultiPoint(pt1,pt2,...)

Constructs a WKB MultiPoint value using WKB Point arguments. If any argument is not a WKBPoint, the return value is NULL.

LineString(pt1,pt2,...)

Constructs a WKB LineString valeu from a number of WKB Point arguments. If any argument is not a WKB Point, the return value is NULL. If the number of Point arguments is less than two, the return value is NULL.

MultiLineString(ls1,ls2,...)

Constructs a WKB MultiLineString value using using WBK LineString arguments. If any argument is not a LineString, the return value is NULL.

Polygon(ls1,ls2,...)

Constructs a WKB Polygon value from a number of WKB LineString arguments. If any argument does not represent the WKB of a LinearRing (that is, not a closed and simple LineString) the return value is NULL.

MultiPolygon(poly1,poly2,...)

Constructs a WKB MultiPolygon value from a set of WKB Polygon arguments. If any argument is not a WKB Polygon, the rerurn value is NULL.

GeometryCollection(g1,g2,...)

Constucts a WKB GeometryCollection. If any argument is not a well-formed WKB representation of a geometry, the return value is NULL.

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