(mysql.info.gz) GIS WKB format

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(mysql.info.gz) GIS WKT format

(mysql.info.gz) Supported spatial data formats

 
 18.3.2 Well-Known Binary (WKB) Format
 -------------------------------------
 
 The Well-Known Binary (WKB) representation for geometric values is
 defined by the OpenGIS specifications.  It is also defined in the ISO
 "SQL/MM Part 3: Spatial" standard.
 
 WKB is used to exchange geometry data as binary streams represented by
 `BLOB' values containing geometric WKB information.
 
 WKB uses one-byte unsigned integers, four-byte unsigned integers, and
 eight-byte double-precision numbers (IEEE 754 format). A byte is eight
 bits.
 
 For example, a WKB value that corresponds to `POINT(1 1)' consists of
 this sequence of 21 bytes (each represented here by two hex digits):
 
      0101000000000000000000F03F000000000000F03F
 
 The sequence may be broken down into these components:
 
      Byte order : 01
      WKB type   : 01000000
      X          : 000000000000F03F
      Y          : 000000000000F03F
 
 Component representation is as follows:
 
    * The byte order may be either 0 or 1 to indicate little-endian or
      big-endian storage. The little-endian and big-endian byte orders
      are also known as Network Data Representation (NDR) and External
      Data Representation (XDR), respectively.
 
    * The WKB type is a code that indicates the geometry type. Values
      from 1 through 7 indicate `Point', `LineString', `Polygon',
      `MultiPoint', `MultiLineString', `MultiPolygon', and
      `GeometryCollection'.
 
    * A `Point' value has X and Y coordinates, each represented as a
      double-precision value.
 
 
 WKB values for more complex geometry values are represented by more
 complex data structures, as detailed in the OpenGIS specification.
 

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(mysql.info.gz) GIS WKT format

(mysql.info.gz) Supported spatial data formats