Question

我有以下两个类定义：

public class Location : Doc
{
    public string Country { get; set; }
    public string Region { get; set; }
    public string City { get; set; }
    public string PostalCode { get; set; }
    public Double Latitude { get; set; }
    public Double Longitude { get; set; }
    public string MetroCode { get; set; }
    public string AreaCode { get; set; }
    public List<IpRange> IpRanges { get; set; }
}

和

public class IpRange
{
    public long Start { get; set; }
    public long End { get; set; }
}

我的索引定义如下：

public class Locations_ByRange : AbstractIndexCreationTask<Location>
{
    public Locations_ByRange()
    {
        Map = locations =>
            from location in locations
            from range in location.IpRanges
            select new
            {
                range.Start,
                range.End
            };
    }
}

然后我尝试按如下方式查询索引：

var queryable = DocumentSession.Query<IpRange, Locations_ByRange>()
                        .FirstOrDefault(x => x.Start <= reverseIp && x.End >= reverseIp) ?? new IpRange();

但是，运行查询时遇到以下错误：

Exception Details: System.InvalidCastException: Unable to cast object of type 'Jodolo.Data.Locations.Location' to type 'Jodolo.Data.Locations.IpRange'.

而且，这是StackTrace：

    [InvalidCastException: Unable to cast object of type 'Jodolo.Data.Locations.Location' to type 'Jodolo.Data.Locations.IpRange'.]
   Raven.Client.Document.InMemoryDocumentSessionOperations.TrackEntity(String key, RavenJObject document, RavenJObject metadata, Boolean noTracking) in c:\Builds\RavenDB-Stable\Raven.Client.Lightweight\Document\InMemoryDocumentSessionOperations.cs:357
   Raven.Client.Document.SessionOperations.QueryOperation.Deserialize(RavenJObject result) in c:\Builds\RavenDB-Stable\Raven.Client.Lightweight\Document\SessionOperations\QueryOperation.cs:167
   System.Linq.WhereSelectListIterator`2.MoveNext() +104
   System.Collections.Generic.List`1..ctor(IEnumerable`1 collection) +381
   System.Linq.Enumerable.ToList(IEnumerable`1 source) +58
   Raven.Client.Document.SessionOperations.QueryOperation.Complete() in c:\Builds\RavenDB-Stable\Raven.Client.Lightweight\Document\SessionOperations\QueryOperation.cs:143
   Raven.Client.Document.AbstractDocumentQuery`2.GetEnumerator() in c:\Builds\RavenDB-Stable\Raven.Client.Lightweight\Document\AbstractDocumentQuery.cs:891
   System.Linq.Enumerable.FirstOrDefault(IEnumerable`1 source) +152
   Raven.Client.Linq.RavenQueryProviderProcessor`1.GetQueryResult(IDocumentQuery`1 finalQuery) in c:\Builds\RavenDB-Stable\Raven.Client.Lightweight\Linq\RavenQueryProviderProcessor.cs:1529
   Raven.Client.Linq.RavenQueryProviderProcessor`1.ExecuteQuery() in c:\Builds\RavenDB-Stable\Raven.Client.Lightweight\Linq\RavenQueryProviderProcessor.cs:1454
   Raven.Client.Linq.RavenQueryProviderProcessor`1.Execute(Expression expression) in c:\Builds\RavenDB-Stable\Raven.Client.Lightweight\Linq\RavenQueryProviderProcessor.cs:1427
   Raven.Client.Linq.RavenQueryProvider`1.Execute(Expression expression) in c:\Builds\RavenDB-Stable\Raven.Client.Lightweight\Linq\RavenQueryProvider.cs:155
   Raven.Client.Linq.RavenQueryProvider`1.System.Linq.IQueryProvider.Execute(Expression expression) in c:\Builds\RavenDB-Stable\Raven.Client.Lightweight\Linq\RavenQueryProvider.cs:198
   System.Linq.Queryable.FirstOrDefault(IQueryable`1 source, Expression`1 predicate) +287

。。

我很高兴看到这一点，因为最终我试图检索满足查询参数的Location文档。很明显，我可以将查询调用的类型声明更改为

.Query<Location, Locations_ByRange>()

但是，我无法弄清楚如何查询存储在索引中的字段;因为没有为Location对象定义Start和End字段。

对此的任何帮助将不胜感激。

Answer 1

将您的查询更改为：

using Raven.Client;

...

var location = session.Query<IpRange, Locations_ByRange>()
                      .Where(x => x.Start <= reverseIp && x.End >= reverseIp)
                      .As<Location>()
                      .FirstOrDefault();

在索引中，您可能需要添加排序提示：

public class Locations_ByRange : AbstractIndexCreationTask<Location, IpRange>
{
    public Locations_ByRange()
    {
        Map = locations =>
            from location in locations
            from range in location.IpRanges
            select new
            {
                range.Start,
                range.End
            };

        Sort(x => x.Start, SortOptions.Long);
        Sort(x => x.End, SortOptions.Long);
    }
}

请注意，我在AbstractIndexCreationTask<Location, IpRange>的顶部添加了返回类型。这将对齐类型，以便Sort方法可以找到这些属性。

ravendb查询locationsbyip索引

1 个答案: