这是'删除'的方式：

This is the 'delete' way:

SET @XML.modify('delete /my/Fields/Fields_1')

原因是 modify 无法仅获取文字的变量。 ..

您可以创建当然动态SQL ...

sp_executesql（Transact-SQL）| Microsoft Docs [ ^ ]

The reason is that modify can not get variables only literal...
You can create of course dynamic SQL...
sp_executesql (Transact-SQL) | Microsoft Docs[^]