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2

So, let's summarize for one piece of geodata. 1) Input data are axial lines of roads of one Amsterdam tablet; 2) The length of red lines is not uniform, it is present either on one side or on two sides of quarters and in some places has the bent form; 3) Distances between the red lines and the green lines are different; 4) When trimming lines at ...


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This is a classic road network conflation problem. It has the following challenges: determining a set of matched road segments to a path line in spite of them being very different lengths clipping the matched road segments to the path line (this is best done after merging the matched road segments (The "path lines" are the red lines in the diagram) For ...


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One option would be to add the default value Incomplete to the STATUS field of the feature class after you truncate it. With arcpy you can do it like this, arcpy.AssignDefaultToField_management( outFeatureClass, 'STATUS', 'Incomplete' ) AcrGIS Docs - Assign default to field


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Got it. Just followed a tutorial available at https://javarevisited.blogspot.com/2012/11/how-to-join-three-tables-in-sql-query-mysql-sqlserver.html and extended the logic from 3 tables to 4. Here follows the code that worked. SELECT users.display_name, current_way_tags.k, users.changesets_count FROM users INNER JOIN changesets ON users.id =...


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You have to select the tables you intend to use in your query first, then the columns names will be displayed (the columns drop down menu will be populated) ...


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You have two alternatives. On the one hand, you can create/read a table from a PostGIS query using ST_Makeline using something like: SELECT ST_MakeLine(the_geom_webmercator ORDER BY track_seg_id ASC) AS the_geom_webmercator, track_fid, row_number() OVER() AS cartodb_id FROM table_name GROUP BY track_fid On the other,...


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In the Execute SQL window (Exécuter SQL), you have to check the layer parameter in the Add additionnal datas (Ajouter des données additionnelles), select no geometry for the ouput geometry type and use the following query : SELECT [% @id %] as CAT, SUM(area(input1.geometry)) as SURF FROM input1 GROUP BY CAT It works but I didn't manage to use the ...


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You can add and manipulate fields in your query SELECT a.com || '_' || b.com as com ST_INTERSECTION(a.geom, b.geom) as geom FROM mytable a, mytable b WHERE a.ID < b.ID AND ST_INTERSECTS(a.geom, b.geom);


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