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Query a Spatial Index

{NOTE: }

  • Documents that contain spatial data can be queried by spatial queries that employ geographical criteria.
    You have two options:

    • Dynamic spatial query
      Either make a dynamic spatial query on a collection (see how to make a spatial query).
      An auto-index will be created by the server.

    • Spatial index query
      Or, index your documents' spatial data in a static-index (see indexing spatial data)
      and then make a spatial query on this index ( described in this article ).

  • A few examples of querying a spatial index are provided below.
    A spatial query performed on a static-index is similar to the dynamic spatial query.
    Find all spatial API methods listed here.

  • Examples in this page:

{NOTE/}

{PANEL: Search by radius}

  • Query the spatial index:

  • Use the WithinRadius method to search for all documents containing spatial data that is located
    within the specified distance from the given center point.

{CODE-TABS} {CODE-TAB:csharp:Query spatial_query_1@Indexes\SpatialIndexes.cs /} {CODE-TAB:csharp:DocumentQuery spatial_query_2@Indexes\SpatialIndexes.cs /} {CODE-TAB:csharp:Index spatial_index_1@Indexes\SpatialIndexes.cs /} {CODE-TAB-BLOCK:sql:RQL} from index "Events/ByNameAndCoordinates" where spatial.within( Coordinates, spatial.circle(20, 47.623473, -122.3060097) )

// The query returns all matching Event entities // that are located within 20 kilometers radius // from point (47.623473 latitude, -122.3060097 longitude). {CODE-TAB-BLOCK/} {CODE-TABS/}

{PANEL/}

{PANEL: Search by shape}

  • Query the spatial index:
    Use the RelatesToShape method to search for all documents containing spatial data that is located
    in the specified relation to the given shape.

  • The shape in the query is specified as either a circle or a polygon in a WKT format.
    See polygon rules here.

  • The relation to the shape can be one of: Within, Contains, Disjoint, Intersects.

  • See more usage examples in the dynamic search by shape query.

{CODE-TABS} {CODE-TAB:csharp:Query spatial_query_3@Indexes\SpatialIndexes.cs /} {CODE-TAB:csharp:DocumentQuery spatial_query_4@Indexes\SpatialIndexes.cs /} {CODE-TAB:csharp:Index spatial_index_2@Indexes\SpatialIndexes.cs /} {CODE-TAB-BLOCK:sql:RQL} from index "EventsWithWKT/ByNameAndWKT" where spatial.within( WKT, spatial.wkt("POLYGON (( -118.6527948 32.7114894, -95.8040242 37.5929338, -102.8344151 53.3349629, -127.5286633 48.3485664, -129.4620208 38.0786067, -118.7406746 32.7853769, -118.6527948 32.7114894))") )

// The query returns all matching Event entities // that are located within the specified polygon. {CODE-TAB-BLOCK/} {CODE-TABS/}

  • Note:
    The index in the above example indexes a WKT string in the spatial index-field.
    However, you can query by shape also on spatial data that is indexed as lat/lng coordinates.

{PANEL/}

{PANEL: Sort results}

  • Query the spatial index:
    Use OrderByDistance or OrderByDistanceDescending to sort the results by distance from a given point.

  • By default, distance in RavenDB measured in kilometers.
    The distance can be rounded to a specific range.

{CODE-TABS} {CODE-TAB:csharp:Query spatial_query_5@Indexes\SpatialIndexes.cs /} {CODE-TAB:csharp:DocumentQuery spatial_query_6@Indexes\SpatialIndexes.cs /} {CODE-TAB:csharp:Index spatial_index_1@Indexes\SpatialIndexes.cs /} {CODE-TAB-BLOCK:sql:RQL} from index "Events/ByNameAndCoordinates" where spatial.within( Coordinates, spatial.circle(20, 47.623473, -122.3060097) ) order by spatial.distance( Coordinates, spatial.point(47.623473, -122.3060097) )

// The query returns all matching Event entities located within 20 kilometers radius // from point (47.623473 latitude, -122.3060097 longitude).

// Sort the results by their distance from a specified point, // the closest results will be listed first. {CODE-TAB-BLOCK/} {CODE-TABS/}

{PANEL/}

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