2018-08-11 15:47:36 +03:00
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# Frequently Asked Questions
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## API Results
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#### 1. The address of my search results contains far-away places that don't belong there.
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Nominatim computes the address from two sources in the OpenStreetMap data:
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from administrative boundaries and from place nodes. Boundaries are the more
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useful source. They precisely describe an area. So it is very clear for
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2019-05-21 14:55:16 +03:00
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Nominatim if a point belongs to an area or not. Place nodes are more complicated.
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These are only points without any precise extent. So Nominatim has to take a
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guess and assume that an address belongs to the closest place node it can find.
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In an ideal world, Nominatim would not need the place nodes but there are
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many places on earth where there are no precise boundaries available for
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2018-08-11 15:47:36 +03:00
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all parts that make up an address. This is in particular true for the more
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local address parts, like villages and suburbs. Therefore it is not possible
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to completely dismiss place nodes. And sometimes they sneak in where they
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don't belong.
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As a OpenStreetMap mapper, you can improve the situation in two ways: if you
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see a place node for which already an administrative area exists, then you
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should _link_ the two by adding the node with a 'label' role to the boundary
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relation. If there is no administrative area, you can add the approximate
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extent of the place and tag it place=<something> as well.
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#### 2. When doing reverse search, the address details have parts that don't contain the point I was looking up.
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There is a common misconception how the reverse API call works in Nominatim.
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Reverse does not give you the address of the point you asked for. Reverse
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returns the closest object to the point you asked for and then returns the
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address of that object. Now, if you are close to a border, then the closest
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object may be across that border. When Nominatim then returns the address,
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it contains the county/state/country across the border.
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#### 3. I get different counties/states/countries when I change the zoom parameter in the reverse query. How is that possible?
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This is basically the same problem as in the previous answer.
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2021-10-18 17:53:24 +03:00
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The zoom level influences at which [search rank](../customize/Ranking.md#search-rank) Nominatim starts looking
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for the closest object. So the closest house number maybe on one side of the
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border while the closest street is on the other. As the address details contain
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the address of the closest object found, you might sometimes get one result,
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sometimes the other for the closest point.
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2018-09-19 20:31:54 +03:00
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#### 4. Can you return the continent?
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Nominatim assigns each map feature one country. Those outside any administrative
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boundaries are assigned a special no-country. Continents or other super-national
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administrations (e.g. European Union, NATO, Custom unions) are not supported,
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see also [Administrative Boundary](https://wiki.openstreetmap.org/wiki/Tag:boundary%3Dadministrative#Super-national_administrations).
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#### 5. Can you return the timezone?
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See this separate OpenStreetMap-based project [Timezone Boundary Builder](https://github.com/evansiroky/timezone-boundary-builder).
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#### 6. I want to download a list of streets/restaurants of a city/region
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The [Overpass API](https://wiki.openstreetmap.org/wiki/Overpass_API) is more
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suited for these kinds of queries.
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That said if you installed your own Nominatim instance you can use the
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`nominatim export` PHP script as basis to return such lists.
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