diff --git a/Src/Asp.Net/SqlSugar/ExpressionsToSql/Subquery/Subquerable.cs b/Src/Asp.Net/SqlSugar/ExpressionsToSql/Subquery/Subquerable.cs
index 3dd5be98b..36d0c7e44 100644
--- a/Src/Asp.Net/SqlSugar/ExpressionsToSql/Subquery/Subquerable.cs
+++ b/Src/Asp.Net/SqlSugar/ExpressionsToSql/Subquery/Subquerable.cs
@@ -185,5 +185,9 @@ namespace SqlSugar
         {
             return default(T);
         }
+        public TResult First<TResult>(Func<T, TResult> selector) where TResult : class, new()
+        {
+            return default(TResult);
+        }
     }
 }