RavenDB地图/按日期分组减少

Question

我必须创建一个查询来获得每年/每月发布的统计信息，例如，按日期分组。我创建一个索引：

public class Posts_Count : AbstractIndexCreationTask<Post, ArchiveItem> 
{ 
    public Posts_Count() 
    { 
     Map = posts => from post in posts 
       select new 
         { 
          Year = post.PublishedOn.Year, 
          Month = post.PublishedOn.Month, 
          Count = 1 
         }; 

     Reduce = results => from result in results 
          group result by new { 
           result.Year, 
           result.Month 
          } 
          into agg 
          select new 
             {            
              Year = agg.Key.Year, 
              Month = agg.Key.Month, 
              Count = agg.Sum(x => x.Count) 
             }; 
    } 
} 

在录音室我有一张地图和减少功能：

地图：

docs.Posts.Select(post => new {Year = post.PublishedOn.Year, Month = post.PublishedOn.Month, Count = 1}) 

减少：

results 
.GroupBy(result => new {Year = result.Year, Month = result.Month}) 
.Select(agg => new {Year = agg.Key.Year, Month = agg.Key.Month, Count = agg.Sum(x => ((System.Int32)(x.Count)))}) 

但问题是我送花儿给人得到年份和月份属性的空值：

{ 
    "Year": null, 
    "Month": null, 
    "Count": "1" 
} 

任何人都可以帮我解决我的代码问题吗？谢谢！

Answer 1

你的代码看起来不错。我测试了它，它在当前不稳定的版本1.2.2096中工作。最近在RavenDB的谷歌群组中有过一些讨论，所以可能以前它被打破了。现在再试一次，看看它现在是否适用于你。