Hi!
I'm completely newbie as it comes to postgis, so forgive me:) - I sent
that question also to postgis mailing list, but here people are faster
in response.
I try to convert my multipolygon layer to multilinestring - here:
http://postgis.refractions.net/docs/ST_ExteriorRing.html
I found example:
"(...)--If you have a table of MULTIPOLYGONs
--and want to return a MULTILINESTRING composed of the exterior rings of
each polygon
SELECT gid, ST_Collect(ST_ExteriorRing(the_geom)) AS erings
FROM (SELECT gid, (ST_Dump(the_geom)).geom As the_geom
FROM sometable) As foo
GROUP BY gid;
(...)"
My postgresql connection calls -"database", schema-"public", default
primary key field - "gid", default geometry field -"geom", my
multipolygon layer- "poly_layer". How will look sql code above, with my
data- if I'd like to convert "poly_layer" into new multilinestring layer
"line_layer"?
Thanks for response
Regarding
Piotr Kania
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