STStartMeasure
STStartMeasure — Returns M value of first point in measured geometry.
Function Specification.
Function STStartMeasure ( @p_linestring geometry ) Returns geometry
Description.
Returns start measure associated with first point in a measured (multi)line-string.
If the line-string is not measured it returns 0.
Supports Linestrings with CircularString elements (2012).
Parameters.
@p_linestring (geometry) - Supplied Linestring geometry.
Result.
This function returns the M ordinate value of first point in a measured line-string.
Example.
select [$(lrsowner)].[STStartMeasure](geometry::STGeomFromText('LINESTRING(1 1 2 3, 2 2 3 4)', 0)) as start_measure union all select [$(lrsowner)].[STStartMeasure](geometry::STGeomFromText('MULTILINESTRING((1 1 2 3, 2 2 3 4),(3 3 4 5,4 4 5 6))', 0)) union all select [$(lrsowner)].[STStartMeasure](geometry::STGeomFromText('CIRCULARSTRING (3 6.325 NULL 0, 0 7 NULL 3.08, -3 6.325 NULL 6.15)',0)) GO start_measure 3 3 0