These properties do not appear in the Expressions window, but can be determined through exploring a data source through a registered data processing extension and its associated query designer.

• 这些属性不会出现在“表达式”窗口中,但是可以通过浏览数据源(通过已注册的数据处理扩展插件及其关联的查询设计器)来加以确定。