to update my database I need to extract some datas from OSM database. To do it I have downloaded the osm pbf file from the website of GEOFABRIK. From this PBF file I wish to extract all the polygons and multipolygons with some key values. My probleme is whatever command line I use with osmosis it seems that I miss the objects with the type multipolygon. To illustrate my problem you will find the command I use for the object with the tag townhall in the keyword amenity.
To do that I have tried some command:
osmosis --read-xml nord-pas-de-calais-latest.osm --way-key-value keyValueList="amenity.townhall" --bounding-box top=50.794448377057 left=2.78824307841151 bottom=50.4995835747462 right=3.2719212468744 --used-node --write-xml #target_file.osm#
OR
osmosis --read-pbf nord-pas-de-calais-latest.osm.pbf --log-progress --tf accept-ways amenity=townhall --bounding-box top=50.794448377057 left=2.78824307841151 bottom=50.4995835747462 right=3.2719212468744 --used-node --write-xml extraction_test_townhall.osm
AND those commands lines
# read all nodes with amenity=townhall or townhall=yes, ignore ways and relations
osmosis --read-xml nord-pas-de-calais-latest.osm --tf accept-nodes amenity=townhall --tf reject-ways --tf reject-relations --write-xml amenity_townhall_nodes.osm
osmosis --read-xml nord-pas-de-calais-latest.osm --tf accept-nodes townhall=yes --tf reject-ways --tf reject-relations --write-xml townhall_yes_nodes.osm
# read all ways with amenity=townhall or townhall=yes, keep only related nodes, ignore relations
osmosis --read-xml nord-pas-de-calais-latest.osm --tf accept-ways amenity=townhall --used-node --tf reject-relations --write-xml amenity_townhall_ways.osm
osmosis --read-xml nord-pas-de-calais-latest.osm --tf accept-ways townhall=yes --used-node --tf reject-relations --write-xml townhall_yes_ways.osm
# read all relations with amenity=townhall or townhall=yes, keep only related ways and nodes
osmosis --read-xml nord-pas-de-calais-latest.osm
--tf accept-relations amenity=townhall --used-way --tf accept-relations townhall=yes --used-node --write-xml amenity_townhall_relations.osm
osmosis --read-xml nord-pas-de-calais-latest.osm --tf accept-relations townhall=yes --used-way --tf accept-relations townhall=yes --used-node --write-xml townhall_yes_relations.osm
# merge all files together
osmosis --rx amenity_townhall_nodes.osm --rx townhall_yes_nodes.osm --rx amenity_townhall_ways.osm --rx C:\Users\rjault\Documents\02_DEMANDE\13_OSM_ORACLE\OSMOSIS\townhall_yes_ways.osm --rx amenity_townhall_relations.osm --rx townhall_yes_relations.osm --merge --merge --merge --merge --merge --wx townhall.osm
It doesn't matter which command I use the result is always the same. You can see on the picture, In green the original dataset and in purple the townhalls I have extracted. The object surrounded in red for exemple is missing in my extraction.
I have also tried the solution brought by AKX but even there, I still miss the biggest townhall of my area. OSM seems to be a really nice database I wish to use it more.
So thank you for your help.
This helped but it keeps a selected set of points which contain both road and building data.