diff --git a/OpenAuth.Repository/Core/StringEntity.cs b/OpenAuth.Repository/Core/StringEntity.cs
index e2d610fa..e77cc08f 100644
--- a/OpenAuth.Repository/Core/StringEntity.cs
+++ b/OpenAuth.Repository/Core/StringEntity.cs
@@ -1,5 +1,6 @@
 using System;
 using System.ComponentModel;
+using SqlSugar;
 
 namespace OpenAuth.Repository.Core
 {
@@ -9,6 +10,7 @@ namespace OpenAuth.Repository.Core
     public class StringEntity : BaseEntity
     {
         [Browsable(false)]
+        [SugarColumn(IsPrimaryKey = true)]
         public string Id { get; set; }
         
         /// <summary>