[postgis-users] sql statements for angles on multilinestrings

[Thomas Preuth]

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Hello,

I have two questions concerning postgis.
The issue is:

The column the_geom includes lines (multilinestring) as geometries, which
define their position by two coordinates. A symbol  should be placed at
first coordinate. The base of the symbol should be perpendicular to the
line. Therefore I need the tilt angle of the multilinestring.
So my questions:
1.)How can I extract the first coordinate of the multilinestring with  a
sql statement?
2.)How can I get the tilt angle of the multilinestring (to the horizontal)
with a sql statement?

Thanks!