Now, regarding your questions: by default, those queries include both nodes, ways. For many use cases the wizard creates useful queries out of the box already. This way you can easily get started with Overpass API without having to deal with all the details. According to the Overpass API, the Overpass. overpass turbo wizard uses a template based approach to create an Overpass QL query. Settings: Things like output format that can be set once at the beginning. The web-based data mining tool Overpass-Turbo4 enables to retrieve data via queries through the Overpass API5. Standalone queries: These are complete statements on their own.įilters: They are always part of a query statement and contain the interesting selectors and filters.īlock statements: They group statements and enable disjunctions as well as loops. This is overpass turbo, a web-based data filtering tool for OpenStreetMap. You almost always need the print statement, which is called an action, because it has an effect outside the execution state (the output). There are several different types of statement. Once a new result is (implicitly or explicitly) assigned to an existing set, its previous contents will be replaced and are no longer available. Names for sets may consist of letters, digits and the underscore but must not start with a digit. Unless you specify a named set as input or result, all input is implicitly read from and all results are written to the default variable named _ (a single underscore). ![]() Using the query wizard, I have build the previous qu. I am trying to retrieve its boundaries from OSM using overpass turbo. It has a C style syntax: The whole query. Catalonia has 42 'counties' which we call " comarques" (example). Sets are created as result sets of statements and are read by subsequent statements as input. Overpass QL is the second query language for the Overpass API and was designed as an alternative to Overpass XML. A set can contain nodes, ways, relations and areas, also of mixed type and of any number. The execution state consists of the default set, potentially other named sets, and for block statements a stack. It has imperative semantics: The statements are processed one after another and change the execution state according to their semantics. It has a C style syntax: The whole query source code is divided in statements, and every statement ends with a semicolon. The following snippet gives an idea how an Overpass API endpoint can be queried with PowerShell: query. Overpass QL is the second query language for the Overpass API and was designed as an alternative to Overpass XML.
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