![]() That demonstrates the use of an area as filter multiple times. We restrict here to an often well-adapted variant:Īrea ( nwr(area) node(w) ) out There are several variants adapted to each downstream use case. This entitles the server to compress the data,Īnd this reduces the data about sevenfold and relieves both ends of the connection.īecause a source of big amounts of unhelpful data are large-scale relations, If you set the additional header Accept-Encoding: gzip, deflate. In both cases do you do to me, to you, and to all the other users a big favor Wget -O -header='Accept-Encoding: gzip, deflate' \ -post-file=london.ql ''Ĭurl -H'Accept-Encoding: gzip, deflate' \ '' \ īoth commands can of course be written without the backslash in a single line. You then can pose requests on the command line with To exercise this, please store one of the queries from above in a local file, e.g. ![]() It might be even easier to use download tools like Wget or Curl. It is normal that nothing happens immediately after the click.ĭownloading entire London can take several minutes. You can in both cases download the raw data directly to your local computer:įor this purpose Overpass Turbo offers in the Export menu the link download as raw OSM data. In addition, for virtually all areas in official boundaries I suggest to rather use regional extracts.ĭetails for this are in the subsection about regional extracts. While Overpass Turbo already from 2000 objects on substantially slows down the browser. This works almost with the request that we have used as a tutorial.įor an area of the size of London, a threshold of 10 million objects or more is easily surpassed, Now we want to download really all data in an area. Overpass Turbo replaces the expression by an id query for the corresponding area, That Overpass Turbo asks Nominatim for the most plausible object for the name London. That the bounding box can be computed automatically with the convenience feature of Overpass Turbo: area nwr(area)( triggers We can draw a huge bounding box around the approximate target regionĪnd can pose the request: area nwr(area)(50.5,-1,52.5,1) out center There are five different ways to make our request more precise. We need to express that we want only the big London in England. This is because there are many areas named London Unexpectedly, many results pop up across half of the planet. That have a tag with key name and value London.īy the way, the whole statement is still a query statement. Line 1 selects all objects of the type area Thus we must first bring our areas of interest into the set _. To those that are partly or completely within one or more of the areas in the set _. The filter (area) there restricts the found objects We first want to display all supermarkets in London: area nwr(area) out center The download of all objects follows in the next subsection. Once the area mechanism is introduced in this section, To get quick responses to requests for exercising the syntax. We start with objects of a rather sparse type, To download all objects of a certain type or all objects in general in a named area of interest. The typical use case for areas in the Overpass API is Thus this change may not happen anytime soon. There are many more pressing issues in the project, There is no specific timetable for also converting the relations. The criterion (pivot) and the statement map_to_area pass closed ways unchanged throughĪnd only convert between the relations and the areas generated from them. ![]() The statement is_in and queries with type area now return closed ways and areas generated from relations.Ĭonversely, the criterion area evaluates both closed ways and generated areas. ![]() Since version 0.7.57, ways have already been changed,īut relations remain with the generated data type for the time being. Thus, I now plan to directly work with the de facto types of closed way and closed relation,īut in the end some of the syntax variants listed here will become outdated.Īs few syntax variants as possible will be removed. I'm nowadays pretty sure that this will never happen. If a datatype for areas ever had appeared. The datatype has been created to remain compatible This does not necessarily apply to the current model of areas: That its content remains valid for many years.
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