12.16.9.2 Spatial Relation Functions That Use Minimum Bounding Rectangles

MySQL provides several MySQL-specific functions that test the relationship between minimum bounding rectangles (MBRs) of two geometries g1 and g2. The return values 1 and 0 indicate true and false, respectively.

A corresponding set of MBR functions defined according to the OpenGIS specification is described later in this section.

• MBRContains(g1, g2)

  Returns 1 or 0 to indicate whether the minimum bounding rectangle of g1 contains the minimum bounding rectangle of g2. This tests the opposite relationship as MBRWithin().

  mysql> SET @g1 = ST_GeomFromText('Polygon((0 0,0 3,3 3,3 0,0 0))');
  mysql> SET @g2 = ST_GeomFromText('Point(1 1)');
  mysql> SELECT MBRContains(@g1,@g2), MBRWithin(@g2,@g1);
  +----------------------+--------------------+
  | MBRContains(@g1,@g2) | MBRWithin(@g2,@g1) |
  +----------------------+--------------------+
  |                    1 |                  1 |
  +----------------------+--------------------+

  MBRContains() and Contains() are synonyms.

• MBRDisjoint(g1, g2)

  Returns 1 or 0 to indicate whether the minimum bounding rectangles of the two geometries g1 and g2 are disjoint (do not intersect).

  MBRDisjoint() and Disjoint() are synonyms.

• MBREqual(g1, g2)

  Returns 1 or 0 to indicate whether the minimum bounding rectangles of the two geometries g1 and g2 are the same.

• MBRIntersects(g1, g2)

  Returns 1 or 0 to indicate whether the minimum bounding rectangles of the two geometries g1 and g2 intersect.

  MBRIntersects() and Intersects() are synonyms.

• MBROverlaps(g1, g2)

  Two geometries spatially overlap if they intersect and their intersection results in a geometry of the same dimension but not equal to either of the given geometries.

  This function returns 1 or 0 to indicate whether the minimum bounding rectangles of the two geometries g1 and g2 overlap.

  MBROverlaps() and Overlaps() are synonyms.

• MBRTouches(g1, g2)

  Two geometries spatially touch if their interiors do not intersect, but the boundary of one of the geometries intersects either the boundary or the interior of the other.

  This function returns 1 or 0 to indicate whether the minimum bounding rectangles of the two geometries g1 and g2 touch.

• MBRWithin(g1, g2)

  Returns 1 or 0 to indicate whether the minimum bounding rectangle of g1 is within the minimum bounding rectangle of g2. This tests the opposite relationship as MBRContains().

  mysql> SET @g1 = ST_GeomFromText('Polygon((0 0,0 3,3 3,3 0,0 0))');
  mysql> SET @g2 = ST_GeomFromText('Polygon((0 0,0 5,5 5,5 0,0 0))');
  mysql> SELECT MBRWithin(@g1,@g2), MBRWithin(@g2,@g1);
  +--------------------+--------------------+
  | MBRWithin(@g1,@g2) | MBRWithin(@g2,@g1) |
  +--------------------+--------------------+
  |                  1 |                  0 |
  +--------------------+--------------------+

  MBRWithin() and Within() are synonyms.

The OpenGIS specification defines the following functions that test the relationship between two geometry values g1 and g2. The MySQL implementation uses minimum bounding rectangles, so these functions return the same result as the corresponding MBR-based functions described earlier in this section. The return values 1 and 0 indicate true and false, respectively.

• Contains(g1, g2)

  MBRContains() and Contains() are synonyms. For more information, see the description of MBRContains().

• Disjoint(g1, g2)

  MBRDisjoint() and Disjoint() are synonyms. For more information, see the description of MBRDisjoint().

• Equals(g1, g2)

  Returns 1 or 0 to indicate whether g1 is spatially equal to g2.

• Intersects(g1, g2)

  MBRIntersects() and Intersects() are synonyms. For more information, see the description of MBRIntersects().

• Overlaps(g1, g2)

  MBROverlaps() and Overlaps() are synonyms. For more information, see the description of MBROverlaps().

• Within(g1, g2)

  MBRWithin() and Within() are synonyms. For more information, see the description of MBRWithin().