If any argument is NULL or any geometry argument is an empty geometry, the return value is NULL.

If any geometry argument is not a syntactically well-formed geometry, an ER_GIS_INVALID_DATA error occurs.

If any geometry argument is a syntactically well-formed geometry in an undefined spatial reference system (SRS), an ER_SRS_NOT_FOUND error occurs.

For functions that take multiple geometry arguments, if those arguments are not in the same SRS, an ER_GIS_DIFFERENT_SRIDS error occurs.

If any geometry argument is geometrically invalid, either the result is true or false (it is undefined which), or an error occurs.

For geographic SRS geometry arguments, if any argument has a longitude or latitude that is out of range, an error occurs:

Ranges shown are in degrees. If an SRS uses another unit, the range uses the corresponding values in its unit. The exact range limits deviate slightly due to floating-point arithmetic.

Otherwise, the return value is non-NULL.

A unit is supported if it is found in the INFORMATION_SCHEMA ST_UNITS_OF_MEASURE table. See Section 28.3.37, “The INFORMATION_SCHEMA ST_UNITS_OF_MEASURE Table”.

If a unit is specified but not supported by MySQL, an ER_UNIT_NOT_FOUND error occurs.

If a supported linear unit is specified and the SRID is 0, an ER_GEOMETRY_IN_UNKNOWN_LENGTH_UNIT error occurs.

If a supported linear unit is specified and the SRID is not 0, the result is in that unit.

If a unit is not specified, the result is in the unit of the SRS of the geometries, whether Cartesian or geographic. Currently, all MySQL SRSs are expressed in meters.

ST_Contains(g1, g2)

Returns 1 or 0 to indicate whether g1 completely contains g2. This tests the opposite relationship as ST_Within().

ST_Contains() handles its arguments as described in the introduction to this section.

ST_Crosses(g1, g2)

Two geometries spatially cross if their spatial relation has the following properties:

This function returns 1 or 0 to indicate whether g1 spatially crosses g2.

ST_Crosses() handles its arguments as described in the introduction to this section except that the return value is NULL for these additional conditions:

ST_Disjoint(g1, g2)

Returns 1 or 0 to indicate whether g1 is spatially disjoint from (does not intersect) g2.

ST_Disjoint() handles its arguments as described in the introduction to this section.

ST_Distance(g1, g2 [, unit])

Returns the distance between g1 and g2, measured in the length unit of the spatial reference system (SRS) of the geometry arguments, or in the unit of the optional unit argument if that is specified.

This function processes geometry collections by returning the shortest distance among all combinations of the components of the two geometry arguments.

ST_Distance() handles its geometry arguments as described in the introduction to this section, with these exceptions:

ST_Distance() permits specifying the linear unit for the returned distance value with an optional unit argument which ST_Distance() handles as described in the introduction to this section.

mysql> SET @g1 = ST_GeomFromText('POINT(1 1)');
mysql> SET @g2 = ST_GeomFromText('POINT(2 2)');
mysql> SELECT ST_Distance(@g1, @g2);
+-----------------------+
| ST_Distance(@g1, @g2) |
+-----------------------+
|    1.4142135623730951 |
+-----------------------+

mysql> SET @g1 = ST_GeomFromText('POINT(1 1)', 4326);
mysql> SET @g2 = ST_GeomFromText('POINT(2 2)', 4326);
mysql> SELECT ST_Distance(@g1, @g2);
+-----------------------+
| ST_Distance(@g1, @g2) |
+-----------------------+
|     156874.3859490455 |
+-----------------------+
mysql> SELECT ST_Distance(@g1, @g2, 'metre');
+--------------------------------+
| ST_Distance(@g1, @g2, 'metre') |
+--------------------------------+
|              156874.3859490455 |
+--------------------------------+
mysql> SELECT ST_Distance(@g1, @g2, 'foot');
+-------------------------------+
| ST_Distance(@g1, @g2, 'foot') |
+-------------------------------+
|             514679.7439273146 |
+-------------------------------+

For the special case of distance calculations on a sphere, see the ST_Distance_Sphere() function.

ST_Equals(g1, g2)

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

ST_Equals() handles its arguments as described in the introduction to this section, except that it does not return NULL for empty geometry arguments.

mysql> SET @g1 = Point(1,1), @g2 = Point(2,2);
mysql> SELECT ST_Equals(@g1, @g1), ST_Equals(@g1, @g2);
+---------------------+---------------------+
| ST_Equals(@g1, @g1) | ST_Equals(@g1, @g2) |
+---------------------+---------------------+
|                   1 |                   0 |
+---------------------+---------------------+

ST_FrechetDistance(g1, g2 [, unit])

Returns the discrete Fréchet distance between two geometries, reflecting how similar the geometries are. The result is a double-precision number measured in the length unit of the spatial reference system (SRS) of the geometry arguments, or in the length unit of the unit argument if that argument is given.

This function implements the discrete Fréchet distance, which means it is restricted to distances between the points of the geometries. For example, given two LineString arguments, only the points explicitly mentioned in the geometries are considered. Points on the line segments between these points are not considered.

ST_FrechetDistance() handles its geometry arguments as described in the introduction to this section, with these exceptions:

ST_FrechetDistance() handles its optional unit argument as described in the introduction to this section.

mysql> SET @ls1 = ST_GeomFromText('LINESTRING(0 0,0 5,5 5)');
mysql> SET @ls2 = ST_GeomFromText('LINESTRING(0 1,0 6,3 3,5 6)');
mysql> SELECT ST_FrechetDistance(@ls1, @ls2);
+--------------------------------+
| ST_FrechetDistance(@ls1, @ls2) |
+--------------------------------+
|             2.8284271247461903 |
+--------------------------------+

mysql> SET @ls1 = ST_GeomFromText('LINESTRING(0 0,0 5,5 5)', 4326);
mysql> SET @ls2 = ST_GeomFromText('LINESTRING(0 1,0 6,3 3,5 6)', 4326);
mysql> SELECT ST_FrechetDistance(@ls1, @ls2);
+--------------------------------+
| ST_FrechetDistance(@ls1, @ls2) |
+--------------------------------+
|              313421.1999416798 |
+--------------------------------+
mysql> SELECT ST_FrechetDistance(@ls1, @ls2, 'foot');
+----------------------------------------+
| ST_FrechetDistance(@ls1, @ls2, 'foot') |
+----------------------------------------+
|                     1028284.7767115477 |
+----------------------------------------+

ST_HausdorffDistance(g1, g2 [, unit])

Returns the discrete Hausdorff distance between two geometries, reflecting how similar the geometries are. The result is a double-precision number measured in the length unit of the spatial reference system (SRS) of the geometry arguments, or in the length unit of the unit argument if that argument is given.

This function implements the discrete Hausdorff distance, which means it is restricted to distances between the points of the geometries. For example, given two LineString arguments, only the points explicitly mentioned in the geometries are considered. Points on the line segments between these points are not considered.

ST_HausdorffDistance() handles its geometry arguments as described in the introduction to this section, with these exceptions:

ST_HausdorffDistance() handles its optional unit argument as described in the introduction to this section.

mysql> SET @ls1 = ST_GeomFromText('LINESTRING(0 0,0 5,5 5)');
mysql> SET @ls2 = ST_GeomFromText('LINESTRING(0 1,0 6,3 3,5 6)');
mysql> SELECT ST_HausdorffDistance(@ls1, @ls2);
+----------------------------------+
| ST_HausdorffDistance(@ls1, @ls2) |
+----------------------------------+
|                                1 |
+----------------------------------+

mysql> SET @ls1 = ST_GeomFromText('LINESTRING(0 0,0 5,5 5)', 4326);
mysql> SET @ls2 = ST_GeomFromText('LINESTRING(0 1,0 6,3 3,5 6)', 4326);
mysql> SELECT ST_HausdorffDistance(@ls1, @ls2);
+----------------------------------+
| ST_HausdorffDistance(@ls1, @ls2) |
+----------------------------------+
|               111319.49079326246 |
+----------------------------------+
mysql> SELECT ST_HausdorffDistance(@ls1, @ls2, 'foot');
+------------------------------------------+
| ST_HausdorffDistance(@ls1, @ls2, 'foot') |
+------------------------------------------+
|                        365221.4264870815 |
+------------------------------------------+

ST_Intersects(g1, g2)

Returns 1 or 0 to indicate whether g1 spatially intersects g2.

ST_Intersects() handles its arguments as described in the introduction to this section.

ST_Overlaps(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 g1 spatially overlaps g2.

ST_Overlaps() handles its arguments as described in the introduction to this section except that the return value is NULL for the additional condition that the dimensions of the two geometries are not equal.

ST_Touches(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 g1 spatially touches g2.

ST_Touches() handles its arguments as described in the introduction to this section except that the return value is NULL for the additional condition that both geometries are of dimension 0 (Point or MultiPoint).

ST_Within(g1, g2)

Returns 1 or 0 to indicate whether g1 is spatially within g2. This tests the opposite relationship as ST_Contains().

ST_Within() handles its arguments as described in the introduction to this section.