(mysql.info.gz) Functions that test spatial relationships between geometries

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(mysql.info.gz) Relations on geometry MBR

(mysql.info.gz) Analysing spatial information

 
 18.5.6 Functions That Test Spatial Relationships Between Geometries
 -------------------------------------------------------------------
 
 The OpenGIS specification defines the following functions. Currently,
 MySQL does not implement them according to the specification. Those that
 are implemented return the same result as the corresponding MBR-based
 functions.  This includes functions in the following list other than
 `Distance()' and `Related()'.
 
 These functions may be implemented in future releases with full support
 for spatial analysis, not just MBR-based support.
 
 The functions operate on two geometry values `g1' and `g2'.
 
 `Contains(G1,G2)'
      Returns 1 or 0 to indicate whether or not G1 completely contains
      G2.
 
 `Crosses(G1,G2)'
      Returns 1 if G1 spatially crosses G2.  Returns `NULL' if `g1' is a
      `Polygon' or a `MultiPolygon', or if G2 is a `Point' or a
      `MultiPoint'.  Otherwise, returns 0.
 
      The term _spatially crosses_ denotes a spatial relation between
      two given geometries that has the following properties:
 
         * The two geometries intersect
 
         * Their intersection results in a geometry that has a dimension
           that is one less than the maximum dimension of the two given
           geometries
 
         * Their intersection is not equal to either of the two given
           geometries
 
 
 `Disjoint(G1,G2)'
      Returns 1 or 0 to indicate whether or not G1 is spatially disjoint
      from (does not intersect) G2.
 
 `Distance(G1,G2)'
      Returns as a double-precision number the shortest distance between
      any two points in the two geometries.
 
 `Equals(G1,G2)'
      Returns 1 or 0 to indicate whether or not G1 is spatially equal to
      G2.
 
 `Intersects(G1,G2)'
      Returns 1 or 0 to indicate whether or not G1 spatially intersects
      G2.
 
 `Overlaps(G1,G2)'
      Returns 1 or 0 to indicate whether or not G1 spatially overlaps G2.
      The term _spatially overlaps_ is used if two geometries intersect
      and their intersection results in a geometry of the same dimension
      but not equal to either of the given geometries.
 
 `Related(G1,G2,PATTERN_MATRIX)'
      Returns 1 or 0 to indicate whether or not the spatial relationship
      specified by PATTERN_MATRIX exists between G1 and G2.  Returns -1
      if the arguments are `NULL'.  The pattern matrix is a string. Its
      specification will be noted here if this function is implemented.
 
 `Touches(G1,G2)'
      Returns 1 or 0 to indicate whether or not G1 spatially touches G2.
      Two geometries _spatially touch_ if the interiors of the
      geometries do not intersect, but the boundary of one of the
      geometries intersects either the boundary or the interior of the
      other.
 
 `Within(G1,G2)'
      Returns 1 or 0 to indicate whether or not G1 is spatially within
      G2.
 
 

Info Catalog

(mysql.info.gz) Relations on geometry MBR

(mysql.info.gz) Analysing spatial information