ST_MMin - Amazon Redshift
SyntaxArgumentsReturn typeExamples
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ST_MMin

ST_MMin returns the minimum m coordinate of an input geometry.

Syntax

ST_MMin(geom)

Arguments

geom

A value of data type GEOMETRY or an expression that evaluates to a GEOMETRY type.

Return type

DOUBLE PRECISION value of the minimum m coordinate.

If geom is empty, then null is returned.

If geom is null, then null is returned.

If geom is a 2D or 3DZ geometry, then null is returned.

Examples

The following SQL returns the smallest m coordinate of a linestring in a 3DM geometry. 

SELECT ST_MMin(ST_GeomFromEWKT('LINESTRING M (0 1 2, 3 4 5, 6 7 8)'));

st_mmin
-----------
  2

The following SQL returns the smallest m coordinate of a linestring in a 4D geometry. 

SELECT ST_MMin(ST_GeomFromEWKT('LINESTRING ZM (0 1 2 3, 4 5 6 7, 8 9 10 11)'));

st_mmin
-----------
  3