Query a Spatial Index


  • 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:


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.

// Define a spatial query on index 'Events_ByNameAndCoordinates'
List<Event> employeesWithinRadius = session
    .Query<Event, Events_ByNameAndCoordinates>()
     // Call 'Spatial' method
    .Spatial(
        // Pass the spatial index-field containing the spatial data
        "Coordinates",
        // Set the geographical area in which to search for matching documents
        // Call 'WithinRadius', pass the radius and the center points coordinates  
        criteria => criteria.WithinRadius(20, 47.623473, -122.3060097))
    .ToList();

// The query returns all matching Event entities
// that are located within 20 kilometers radius
// from point (47.623473 latitude, -122.3060097 longitude).
// Define a spatial query on index 'Events_ByNameAndCoordinates'
List<Event> employeesWithinRadius = session.Advanced
    .DocumentQuery<Event, Events_ByNameAndCoordinates>()
     // Call 'Spatial' method
    .Spatial(
        // Pass the spatial index-field containing the spatial data
        "Coordinates",
        // Set the geographical area in which to search for matching documents
        // Call 'WithinRadius', pass the radius and the center points coordinates  
        criteria => criteria.WithinRadius(20, 47.623473, -122.3060097))
    .ToList();

// The query returns all matching Event entities
// that are located within 20 kilometers radius
// from point (47.623473 latitude, -122.3060097 longitude).
// Define an index with a spatial field
public class Events_ByNameAndCoordinates : AbstractIndexCreationTask<Event>
{
    public Events_ByNameAndCoordinates()
    {
        Map = events => from e in events
            select new
            {
                Name = e.Name,
                // Call 'CreateSpatialField' to create a spatial index-field
                // Field 'Coordinates' will be composed of lat & lng supplied from the document
                Coordinates = CreateSpatialField(e.Latitude, e.Longitude)
                
                // Documents can be retrieved
                // by making a spatial query on the 'Coordinates' index-field
            };
    }
}

public class Event
{
    public string Id { get; set; }
    public string Name { get; set; }
    public double Latitude { get; set; }
    public double Longitude { get; set; }
}
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).

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.

// Define a spatial query on index 'EventsWithWKT_ByNameAndWKT'
List<EventWithWKT> employeesWithinShape = session
    .Query<EventWithWKT, EventsWithWKT_ByNameAndWKT>()
    // Call 'Spatial' method
    .Spatial(
        // Pass the spatial index-field containing the spatial data
        "WKT",
        // Set the geographical search criteria, call 'RelatesToShape'
        criteria => criteria.RelatesToShape(
            // Specify the WKT string
            shapeWkt: @"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
                      ))",
            // Specify the relation between the WKT shape and the documents spatial data
            relation: SpatialRelation.Within))
    .ToList();

// The query returns all matching Event entities
// that are located within the specified polygon.
// Define a spatial query on index 'EventsWithWKT_ByNameAndWKT'
List<EventWithWKT> employeesWithinShape = session.Advanced
    .DocumentQuery<EventWithWKT, EventsWithWKT_ByNameAndWKT>()
    // Call 'Spatial' method
    .Spatial(
        // Pass the spatial index-field containing the spatial data
        "WKT",
        // Set the geographical search criteria, call 'RelatesToShape'
        criteria => criteria.RelatesToShape(
            // Specify the WKT string
            shapeWkt: @"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
                      ))",
            // Specify the relation between the WKT shape and the documents spatial data
            relation: SpatialRelation.Within))
    .ToList();

// The query returns all matching Event entities
// that are located within the specified polygon.
// Define an index with a spatial field
public class EventsWithWKT_ByNameAndWKT : AbstractIndexCreationTask<EventWithWKT>
{
    public EventsWithWKT_ByNameAndWKT()
    {
        Map = events => from e in events
            select new
            {
                Name = e.Name,
                // Call 'CreateSpatialField' to create a spatial index-field
                // Field 'WKT' will be composed of the WKT string supplied from the document
                WKT = CreateSpatialField(e.WKT)

                // Documents can be retrieved
                // by making a spatial query on the 'WKT' index-field
            };
    }
}

public class EventWithWKT
{
    public string Id { get; set; }
    public string Name { get; set; }
    public string WKT { get; set; }
}
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.
  • 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.

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.

// Define a spatial query on index 'Events_ByNameAndCoordinates'
List<Event> employeesSortedByDistance = session
    .Query<Event, Events_ByNameAndCoordinates>()
     // Filter results by geographical criteria
    .Spatial(
        "Coordinates",
        criteria => criteria.WithinRadius(20, 47.623473, -122.3060097))
     // Sort results, call 'OrderByDistance'
    .OrderByDistance(
        // Pass the spatial index-field containing the spatial data
        "Coordinates",
        // Sort the results by their distance from this point: 
        47.623473, -122.3060097)
    .ToList();

// Return 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.
// Define a spatial query on index 'Events_ByNameAndCoordinates'
List<Event> employeesSortedByDistance = session.Advanced
    .DocumentQuery<Event, Events_ByNameAndCoordinates>()
     // Filter results by geographical criteria
    .Spatial(
        "Coordinates",
        criteria => criteria.WithinRadius(20, 47.623473, -122.3060097))
     // Sort results, call 'OrderByDistance'
    .OrderByDistance(
        // Pass the spatial index-field containing the spatial data
        "Coordinates",
        // Sort the results by their distance from this point: 
        47.623473, -122.3060097)
    .ToList();

// Return 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.
// Define an index with a spatial field
public class Events_ByNameAndCoordinates : AbstractIndexCreationTask<Event>
{
    public Events_ByNameAndCoordinates()
    {
        Map = events => from e in events
            select new
            {
                Name = e.Name,
                // Call 'CreateSpatialField' to create a spatial index-field
                // Field 'Coordinates' will be composed of lat & lng supplied from the document
                Coordinates = CreateSpatialField(e.Latitude, e.Longitude)
                
                // Documents can be retrieved
                // by making a spatial query on the 'Coordinates' index-field
            };
    }
}

public class Event
{
    public string Id { get; set; }
    public string Name { get; set; }
    public double Latitude { get; set; }
    public double Longitude { get; set; }
}
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.