Add constraints （Updateable）

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

@@ -32,6 +32,7 @@ namespace SqlSugar
         }
         private string _ExecuteCommand()
         {
+            CheckWhere();
             PreToSql();
             AutoRemoveDataCache();
             Check.Exception(UpdateBuilder.WhereValues.IsNullOrEmpty() && GetPrimaryKeys().IsNullOrEmpty(), "You cannot have no primary key and no conditions");
@@ -42,6 +43,14 @@ namespace SqlSugar
             return sql;
         }
 
+        private void CheckWhere()
+        {
+            if (UpdateParameterIsNull && UpdateBuilder.WhereValues.IsNullOrEmpty()) 
+            {
+                Check.ExceptionEasy("Update requires conditions", "更新需要条件 Where");
+            }
+        }
+
         private void _WhereColumn(string columnName)
         {
             var columnInfos = columns.Where(it => it.DbColumnName.Equals(columnName, StringComparison.OrdinalIgnoreCase) || it.PropertyName.Equals(columnName, StringComparison.OrdinalIgnoreCase)).ToList();

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

@@ -18,6 +18,10 @@ namespace SqlSugar
         public UpdateBuilder UpdateBuilder { get; set; }
         public IAdo Ado { get { return Context.Ado; } }
         public T[] UpdateObjs { get; set; }
+        /// <summary>
+        /// true : by expression  update
+        /// false: by object update
+        /// </summary>
         public bool UpdateParameterIsNull { get; set; }
         public bool IsMappingTable { get { return this.Context.MappingTables != null && this.Context.MappingTables.Any(); } }
         public bool IsMappingColumns { get { return this.Context.MappingColumns != null && this.Context.MappingColumns.Any(); } }