RavenDb對以百萬爲單位的文檔查詢性能的期望

Question

我能夠使用嵌入式版本的RavenDb加載幾百萬個文檔，非常漂亮！

現在我試圖查詢這些項目，並發現性能不是我所期望的，如果可能的話，幾乎是瞬間的，但是在一臺相當健壯的機器上可以達到18秒。

下面，你會發現我的樸素代碼。

注意：我現在已經解決了這個問題，最終的代碼位於帖子的底部。帶走的是你需要索引，它們必須是正確的類型，並且需要讓RavenDB知道它們。非常滿意通過查詢引擎返回記錄的性能和質量。

謝謝 斯蒂芬

using (var store = new EmbeddableDocumentStore { DataDirectory = @"C:\temp\ravendata" }.Initialize()) 
{ 
    using (IDocumentSession session = store.OpenSession()) 
    { 
     var q = session.Query<Product>().Where(x => x.INFO2.StartsWith("SYS")).ToList(); 
    } 
} 


[Serializable] 
public class Product 
{ 
    public decimal ProductId { get; set; } 
    .... 
    public string INFO2 { get; set; } 
} 

編輯

我加入這個類

public class InfoIndex_Search : AbstractIndexCreationTask<Product> 
{ 
    public InfoIndex_Search() 
    { 
     Map = products => 
      from p in products 
          select new { Info2Index = p.INFO2 }; 

     Index(x => x.INFO2, FieldIndexing.Analyzed); 
    } 
} 

，改變調用方法看起來像這樣。

 using (var store = new EmbeddableDocumentStore { DataDirectory = @"C:\temp\ravendata" }.Initialize()) 
     { 
      // Tell Raven to create our indexes. 
      IndexCreation.CreateIndexes(Assembly.GetExecutingAssembly(), store); 

      List<Product> q = null; 
      using (IDocumentSession session = store.OpenSession()) 
      { 
       q = session.Query<Product>().Where(x => x.INFO2.StartsWith("SYS")).ToList(); 
       watch.Stop(); 
      } 
     } 

但我仍然報告18秒做搜索。我錯過了什麼？在另一個說明中，C：\ temp \ ravendata \ Indexes \ InfoIndex％2fSearch文件夾中有很多新文件，雖然不像插入數據時那麼多，但它們在運行此代碼後似乎都消失了幾次嘗試查詢。如果IndexCreation.CreateIndexes（Assembly.GetExecutingAssembly（），store）;在插入之前調用，只有這樣？

EDIT1

使用此代碼我能得到查詢的一個實例幾乎要發生，但似乎你只能運行一次此，這樣引出了一個問題。在哪裏運行，什麼是正確的初始化程序？

store.DatabaseCommands.PutIndex("ProdcustByInfo2", new IndexDefinitionBuilder<Product> 
{ 
    Map = products => from product in products 
         select new { product.INFO2 }, 
    Indexes = 
      { 
       { x => x.INFO2, FieldIndexing.Analyzed} 
      } 
}); 

EDIT2：工作示例

static void Main() 
{ 
    Stopwatch watch = Stopwatch.StartNew(); 

    int q = 0; 
    using (var store = new EmbeddableDocumentStore { DataDirectory = @"C:\temp\ravendata" }.Initialize()) 
    { 
     if (store.DatabaseCommands.GetIndex("ProdcustByInfo2") == null) 
     { 
      store.DatabaseCommands.PutIndex("ProdcustByInfo2", new IndexDefinitionBuilder<Product> 
      { 
       Map = products => from product in products 
            select new { product.INFO2 }, 
       Indexes = { { x => x.INFO2, FieldIndexing.Analyzed } } 
      }); 
     } 
     watch.Stop(); 
     Console.WriteLine("Time elapsed to create index {0}{1}", watch.ElapsedMilliseconds, System.Environment.NewLine); 

     watch = Stopwatch.StartNew();    
     using (IDocumentSession session = store.OpenSession()) 
     { 
      q = session.Query<Product>().Count(); 
     } 
     watch.Stop(); 
     Console.WriteLine("Time elapsed to query for products values {0}{1}", watch.ElapsedMilliseconds, System.Environment.NewLine); 
     Console.WriteLine("Total number of products loaded: {0}{1}", q, System.Environment.NewLine); 

     if (q == 0) 
     { 
      watch = Stopwatch.StartNew(); 
      var productsList = Parsers.GetProducts().ToList(); 
      watch.Stop(); 
      Console.WriteLine("Time elapsed to parse: {0}{1}", watch.ElapsedMilliseconds, System.Environment.NewLine); 
      Console.WriteLine("Total number of items parsed: {0}{1}", productsList.Count, System.Environment.NewLine); 

      watch = Stopwatch.StartNew(); 
      productsList.RemoveAll(_ => _ == null); 
      watch.Stop(); 
      Console.WriteLine("Time elapsed to remove null values {0}{1}", watch.ElapsedMilliseconds, System.Environment.NewLine); 
      Console.WriteLine("Total number of items loaded: {0}{1}", productsList.Count, System.Environment.NewLine); 

      watch = Stopwatch.StartNew(); 
      int batch = 0; 
      var session = store.OpenSession(); 
      foreach (var product in productsList) 
      { 
       batch++; 
       session.Store(product); 
       if (batch % 128 == 0) 
       { 
        session.SaveChanges(); 
        session.Dispose(); 
        session = store.OpenSession(); 
       } 
      } 
      session.SaveChanges(); 
      session.Dispose(); 
      watch.Stop(); 
      Console.WriteLine("Time elapsed to populate db from collection {0}{1}", watch.ElapsedMilliseconds, System.Environment.NewLine); 
     } 

     watch = Stopwatch.StartNew(); 
     using (IDocumentSession session = store.OpenSession()) 
     { 
      q = session.Query<Product>().Where(x => x.INFO2.StartsWith("SYS")).Count(); 
     } 
     watch.Stop(); 
     Console.WriteLine("Time elapsed to query for term {0}{1}", watch.ElapsedMilliseconds, System.Environment.NewLine); 
     Console.WriteLine("Total number of items found: {0}{1}", q, System.Environment.NewLine); 
    } 
    Console.ReadLine(); 
} 

Answer 1

首先，你必須覆蓋INFO2的指數？

其次，看到丹尼爾郎鹹平的「搜索在RavenDB字符串屬性」此處的博客文章：

http://daniellang.net/searching-on-string-properties-in-ravendb/

如果有幫助，這裏就是我創建的索引：

public class LogMessageCreatedTime : AbstractIndexCreationTask<LogMessage> 
{ 
    public LogMessageCreatedTime() 
    { 
     Map = messages => from message in messages 
          select new { MessageCreatedTime = message.MessageCreatedTime }; 
    } 
} 

又如何我在運行時添加了它：

private static DocumentStore GetDatabase() 
{    
    DocumentStore documentStore = new DocumentStore();    

    try 
    { 
     documentStore.ConnectionStringName = "RavenDb";     
     documentStore.Initialize(); 

     // Tell Raven to create our indexes. 
     IndexCreation.CreateIndexes(typeof(DataAccessFactory).Assembly, documentStore); 
    } 
    catch 
    { 
     documentStore.Dispose(); 
     throw; 
    } 

    return documentStore; 
} 

就我而言，我不必明確查詢索引;當我正常查詢時才使用它。

Answer 2

正如Bob所暗示的那樣，您應該確保您在Raven中創建了涵蓋您打算查詢的字段的索引。

烏鴉非常快，可以讓你走很長的路，而不需要做太多。 然而，一旦你開始進入大文件號碼，或者需要非默認的東西，你會發現你需要靜態索引。

在Raven中有很多關於設置和使用索引的示例。