[postgis-users] Query to create 2-pt linestrings from Multilinestrings running very very very slow

[Ruth Simm]

Hi all,
I began running this query on a table with 19,763 rows...and it is taking forever (up to 14 hours and still running). I was wondering if there was any other way to optimize this... (note: without creating edges with Topology - which is equally slow)? 
Thank you for your time.

Specs:PostgreSQL 9.2.4PostGis 2.1.0
SELECT row_number() OVER() new_id, geom 
INTO linestrings FROM
  (SELECT 
    (ST_Dump(ST_Node(ST_Union(geom)))).geom geom 
  FROM multlinestrings) a;

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