Spatial functions can be used to determine the spatial relationships between geometries.

  • ST_Contains: returns 1 if g1 completely contains g2.
  • ST_Crosses: returns 1 if the left geometry spatially crosses the right one.
  • ST_Disjoint: returns 1 if the left geometry is spatially disjoint from the right one.
  • ST_Equals: returns 1 if the left geometry is spatially equal to the right one.
  • ST_Intersects: returns 1 if the left geometry spatially intersects the right one.
  • ST_Overlaps: returns 0 if the left geometry spatially overlaps the right one.
  • ST_Relate: returns 1 if the left and right geometries meet the conditions specified by a Dimensionally Extended 9 Intersection Model (DE-9IM) matrix. A third input of the VARCHAR type indicates that the relationship is accepted.
  • ST_Touches: returns 1 if the left geometry spatially touches the right one.
  • ST_Within: returns 1 if the left geometry is spatially enclosed within the right one.

ST_Contains 

ST_Contains(g1, g2)
  • Description: This function returns 1 if g1 completely contains g2. A value of 1 indicates true, and a value of 0 indicates false.
    Note g1 does not contain its boundary.
  • Data type of the return value: INT.
  • Example:
    SELECT ST_Contains(ST_GeometryFromText('POLYGON ((1 1, 1 4, 4 4, 4 1))'), ST_GeometryFromText('POINT (2 2)'));
    Returned results:
    +-----------------------------------------------------------------------------------------------------+
|ST_Contains(ST_GeometryFromText('POLYGON ((1 1, 1 4, 4 4, 4 1))'), ST_GeometryFromText('POINT (2 2)')) |
+-----------------------------------------------------------------------------------------------------+
|                           1                                                                         |

ST_Crosses 

ST_Crosses(g1, g2)
  • Description: This function returns 1 if the left geometry spatially crosses the right one. A value of 1 indicates true, and a value of 0 indicates false.
  • Data type of the return value: INT.
  • Example: 
    SELECT ST_Crosses(ST_GeometryFromText('POINT (20 20)'), ST_GeometryFromText('POINT (25 25)'));
    Returned results:
    +----------------------------------------------------------------------------------------------+
|ST_Crosses(ST_GeometryFromText('POINT (20 20)'), ST_GeometryFromText('POINT (25 25)'))        |
+----------------------------------------------------------------------------------------------+   
|                 0                                                                            |

ST_Disjoint 

ST_Disjoint(g1, g2)
  • Description: This function returns 1 if the left geometry is spatially disjoint from the right one. A value of 1 indicates true, and a value of 0 indicates false.
  • Data type of the return value: INT.
  • Example: 
    SELECT ST_Disjoint(ST_GeometryFromText('POINT (50 100)'), ST_GeometryFromText('POINT (150 150)'));
    Returned results:
    +--------------------------------------------------------------------------------------------------+
|ST_Disjoint(ST_GeometryFromText('POINT (50 100)'), ST_GeometryFromText('POINT (150 150)'))        |
+--------------------------------------------------------------------------------------------------+   
|                        1                                                                         |

ST_Equals

ST_Equals(g1, g2)
  • Description: This function returns 1 if the left geometry is spatially equal to the right one. A value of 1 indicates true, and a value of 0 indicates false.
  • Data type of the return value: INT.
  • Example: 
    SELECT ST_Equals(ST_GeometryFromText('POINT (50 100)'), ST_GeometryFromText('POINT (150 150)'));
    Returned results:
    +------------------------------------------------------------------------------------------------+
|ST_Equals(ST_GeometryFromText('POINT (50 100)'), ST_GeometryFromText('POINT (150 150)'))        |
+------------------------------------------------------------------------------------------------+   
|                  0                                                                             |

ST_Intersects

ST_Intersects(g1, g2)
  • Description: This function returns 1 if the left geometry spatially intersects the right one. A value of 1 indicates true, and a value of 0 indicates false.
  • Data type of the return value: INT.
  • Example: 
    SELECT ST_Intersects(ST_GeometryFromText('POINT (50 100)'), ST_GeometryFromText('POINT (150 150)'));
    Returned results:
    +----------------------------------------------------------------------------------------------------+
|ST_Intersects(ST_GeometryFromText('POINT (50 100)'), ST_GeometryFromText('POINT (150 150)'))        |
+----------------------------------------------------------------------------------------------------+   
|                 0                                                                                  |

ST_Overlaps

ST_Overlaps(g1, g2)
  • Description: This function returns 0 if the left geometry spatially overlaps the right one. A value of 0 indicates true, and a value of 1 indicates false.
  • Data type of the return value: INT.
  • Example: 
    SELECT ST_Overlaps(ST_GeometryFromText('POLYGON ((1 1, 1 4, 4 4, 4 1))'), ST_GeometryFromText('POLYGON ((3 3, 3 5, 5 5, 5 3))'));
    Returned results:
    +---------------------------------------------------------------------------------------------------------------------------------+
|ST_Overlaps(ST_GeometryFromText('POLYGON ((1 1, 1 4, 4 4, 4 1))'), ST_GeometryFromText('POLYGON ((3 3, 3 5, 5 5, 5 3))'))        |
+---------------------------------------------------------------------------------------------------------------------------------+   
|                 1                                                                                                               |

ST_Relate

ST_Relate(g1, g2, s1)
  • Description: This function returns 1 if the left and right geometries meet the conditions specified by a DE-9IM matrix. A value of 1 indicates true, and a value of 0 indicates false. A third input of the VARCHAR type indicates that the relationship is accepted.
  • Data type of the return value: INT.
  • Example: 
    SELECT ST_Relate(ST_GeometryFromText('LINESTRING (0 0, 3 3)'), ST_GeometryFromText('LINESTRING (1 1, 4 1)'), '****T****');
    Returned results:
    +--------------------------------------------------------------------------------------------------------------------------+
|ST_Relate(ST_GeometryFromText('LINESTRING (0 0, 3 3)'), ST_GeometryFromText('LINESTRING (1 1, 4 1)'), '****T****')        |
+--------------------------------------------------------------------------------------------------------------------------+   
|                 0                                                                                                        |

ST_Touches

ST_Touches(g1, g2)
  • Description: This function returns 1 if the left geometry spatially touches the right one. A value of 1 indicates true, and a value of 0 indicates false.
  • Data type of the return value: INT.
  • Example: 
    SELECT ST_Touches(ST_GeometryFromText('POINT (50 100)'), ST_GeometryFromText('POINT (150 150)'));
    Returned results:
    +-------------------------------------------------------------------------------------------------+
|ST_Touches(ST_GeometryFromText('POINT (50 100)'), ST_GeometryFromText('POINT (150 150)'))        |
+-------------------------------------------------------------------------------------------------+   
|                     0                                                                           |

ST_Within

ST_Within(g1, g2)
  • Description: This function returns 1 if the left geometry is spatially enclosed within the right one. A value of 1 indicates true, and a value of 0 indicates false.
  • Data type of the return value: BOOLEAN.
  • Example: 
    SELECT ST_Within(ST_GeometryFromText('POINT (50 100)'), ST_GeometryFromText('POINT (150 150)'))
    Returned results:
    +-------------------------------------------------------------------------------------------------+
|ST_Within(ST_GeometryFromText('POINT (50 100)'), ST_GeometryFromText('POINT (150 150)'))         |
+-------------------------------------------------------------------------------------------------+   
|                 0                                                                               |