Create index manually instead of from ogr2ogr

Because ogr2ogr sets the index name which leads to name clashes on
update. If we let PostgreSQL choose the name we don't have this problem.

Author: joto

themes/external/download-and-import.sh

@@ -61,13 +61,18 @@ import() {
     local file="$3"
     local inlayer="$4"
 
+    # Spatial index is created manually after import, because otherwise
+    # the index names generated by ogr2ogr clash with the preexisting index.
+
     ogr2ogr -f PostgreSQL "PG:dbname=$db" -overwrite -nln "${layer}_new" \
         -lco GEOMETRY_NAME=geom \
         -lco FID=id \
+        -lco SPATIAL_INDEX=NONE \
         -sql 'select "_ogr_geometry_" from '"$inlayer" \
         "/vsizip/$file.zip/$file"
 
     psql --quiet -d "$DB" -c "ANALYZE ${layer}_new;"
+    psql --quiet -d "$DB" -c "CREATE INDEX ON ${layer}_new USING GIST (geom);"
     psql --quiet -d "$DB" -c "BEGIN; DROP TABLE IF EXISTS $layer; ALTER TABLE ${layer}_new RENAME TO $layer; COMMIT;"
 }