From c1180d3a4facfc1e1555ef137c4100d610ad9bb4 Mon Sep 17 00:00:00 2001
From: Marco Minerva <marco.minerva@gmail.com>
Date: Fri, 19 Jul 2024 11:01:44 +0200
Subject: [PATCH] Optimize chunks retrieval

---
 SqlDatabaseVectorSearch/Services/ChatService.cs         | 5 ++---
 SqlDatabaseVectorSearch/Services/VectorSearchService.cs | 1 +
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/SqlDatabaseVectorSearch/Services/ChatService.cs b/SqlDatabaseVectorSearch/Services/ChatService.cs
index cbadcc4..17ed62f 100644
--- a/SqlDatabaseVectorSearch/Services/ChatService.cs
+++ b/SqlDatabaseVectorSearch/Services/ChatService.cs
@@ -2,7 +2,6 @@
 using Microsoft.Extensions.Caching.Memory;
 using Microsoft.Extensions.Options;
 using Microsoft.SemanticKernel.ChatCompletion;
-using SqlDatabaseVectorSearch.DataAccessLayer.Entities;
 using SqlDatabaseVectorSearch.Settings;
 
 namespace SqlDatabaseVectorSearch.Services;
@@ -34,7 +33,7 @@ public class ChatService(IMemoryCache cache, IChatCompletionService chatCompleti
         return reformulatedQuestion.Content!;
     }
 
-    public async Task<string> AskQuestionAsync(Guid conversationId, IEnumerable<DocumentChunk> chunks, string question)
+    public async Task<string> AskQuestionAsync(Guid conversationId, IEnumerable<string> chunks, string question)
     {
         var chat = new ChatHistory(""""
             """
@@ -51,7 +50,7 @@ public class ChatService(IMemoryCache cache, IChatCompletionService chatCompleti
             """);
 
         // TODO: Ensure that chunks are not too long, according to the model max token.
-        foreach (var result in chunks.Select(c => c.Content))
+        foreach (var result in chunks)
         {
             prompt.AppendLine(result);
             prompt.AppendLine("---");
diff --git a/SqlDatabaseVectorSearch/Services/VectorSearchService.cs b/SqlDatabaseVectorSearch/Services/VectorSearchService.cs
index 9936636..4968c98 100644
--- a/SqlDatabaseVectorSearch/Services/VectorSearchService.cs
+++ b/SqlDatabaseVectorSearch/Services/VectorSearchService.cs
@@ -104,6 +104,7 @@ public class VectorSearchService(ApplicationDbContext dbContext, ITextEmbeddingG
 
         var chunks = await dbContext.DocumentChunks
             .OrderBy(c => EF.Functions.VectorDistance("cosine", c.Embedding, questionEmbedding.ToArray()))
+            .Select(c => c.Content)
             .Take(appSettings.MaxRelevantChunks)
             .ToListAsync();