diff --git a/Src/Asp.NetCore2/SqlSugar/Abstract/FastestProvider/Private.cs b/Src/Asp.NetCore2/SqlSugar/Abstract/FastestProvider/Private.cs
index 55b8f7174..8d55dced2 100644
--- a/Src/Asp.NetCore2/SqlSugar/Abstract/FastestProvider/Private.cs
+++ b/Src/Asp.NetCore2/SqlSugar/Abstract/FastestProvider/Private.cs
@@ -179,11 +179,11 @@ namespace SqlSugar
             DataTable tempDataTable = null;
             if (AsName == null)
             {
-                tempDataTable=queryable.Where(it => false).Select("*").ToDataTable();
+                tempDataTable=queryable.Clone().Where(it => false).Select("*").ToDataTable();
             }
             else
             {
-                tempDataTable=queryable.AS(AsName).Where(it => false).Select("*").ToDataTable();
+                tempDataTable=queryable.Clone().AS(AsName).Where(it => false).Select("*").ToDataTable();
             };
             List<string> uInt64TypeName = new List<string>();
             foreach (DataColumn item in tempDataTable.Columns)