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16.4.2.3 Creating Geometry Values Using MySQL-Specific Functions »
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16.4.2.2. Creating Geometry Values Using WKB Functions

MySQL provides a number of functions that take as arguments a BLOB containing a Well-Known Binary representation and, optionally, a spatial reference system identifier (SRID). They return the corresponding geometry.

GeomFromWKB() accepts a WKB 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.

The OpenGIS specification also describes optional functions for constructing Polygon or MultiPolygon values based on the WKB representation of a collection of rings or closed LineString values. These values may intersect. MySQL does not implement these functions:

  • BdMPolyFromWKB(wkb,srid)

    Constructs a MultiPolygon value from a MultiLineString value in WKB format containing an arbitrary collection of closed LineString values.

  • BdPolyFromWKB(wkb,srid)

    Constructs a Polygon value from a MultiLineString value in WKB format containing an arbitrary collection of closed LineString values.