From cde7446d325def8730552d53133d90db64bca7c3 Mon Sep 17 00:00:00 2001
From: Huang Tao <htve@outlook.com>
Date: Fri, 27 Oct 2023 16:02:10 +0800
Subject: [PATCH] performance: multiple attach on Update with EfCore

---
 .../Repositories/EntityFrameworkCore/EfCoreRepository.cs | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/framework/src/Volo.Abp.EntityFrameworkCore/Volo/Abp/Domain/Repositories/EntityFrameworkCore/EfCoreRepository.cs b/framework/src/Volo.Abp.EntityFrameworkCore/Volo/Abp/Domain/Repositories/EntityFrameworkCore/EfCoreRepository.cs
index 3274360ba2..d73e18615d 100644
--- a/framework/src/Volo.Abp.EntityFrameworkCore/Volo/Abp/Domain/Repositories/EntityFrameworkCore/EfCoreRepository.cs
+++ b/framework/src/Volo.Abp.EntityFrameworkCore/Volo/Abp/Domain/Repositories/EntityFrameworkCore/EfCoreRepository.cs
@@ -161,16 +161,17 @@ public class EfCoreRepository<TDbContext, TEntity> : RepositoryBase<TEntity>, IE
     {
         var dbContext = await GetDbContextAsync();
 
-        dbContext.Attach(entity);
-
-        var updatedEntity = dbContext.Update(entity).Entity;
+        if (dbContext.Set<TEntity>().Local.All(e => e != entity))
+        {
+            dbContext.Update(entity);
+        }
 
         if (autoSave)
         {
             await dbContext.SaveChangesAsync(GetCancellationToken(cancellationToken));
         }
 
-        return updatedEntity;
+        return entity;
     }
 
     public async override Task UpdateManyAsync(IEnumerable<TEntity> entities, bool autoSave = false, CancellationToken cancellationToken = default)