update GetDiffTable

Src/Asp.Net/SqlServerTest/Demo/DemoB_Aop.cs

@@ -68,6 +68,9 @@ namespace OrmTest
 
 
             db.Updateable<Order>().SetColumns(it=>it.Name=="asdfa").Where(it=>it.Id==1).EnableDiffLogEvent("--update Order--").ExecuteCommand();
+
+            db.Updateable<Order>().SetColumns(it => it.Name == "asdfa")
+                .Where(it =>SqlFunc.Subqueryable<Order>().Where(x=>x.Id==it.Id).Any()).EnableDiffLogEvent("--update Order--").ExecuteCommand();
             Console.WriteLine("#### Aop End ####");
         }
     }

Src/Asp.Net/SqlSugar/Abstract/UpdateProvider/UpdateableProvider.cs

@@ -840,6 +840,10 @@ namespace SqlSugar
             if (this.UpdateParameterIsNull)
             {
                 var whereSql = Regex.Replace(sql, ".* WHERE ", "", RegexOptions.Singleline);
+                if (sql.Contains("WHERE (EXISTS")) 
+                {
+                    whereSql=Regex.Match(sql, @"\(EXISTS.+").Value;
+                }
                 dt = this.Context.Queryable<T>().Where(whereSql).AddParameters(parameters).ToDataTable();
             }
             else