If you want to introduce a new attribute, you should pick an identifier key that is not already assigned to another attribute.

如果希望引入一个新属性，那么应当挑选一个还没有指定给其他属性的标识符键。

youdao

If you want to introduce a new attribute, you should pick an identifier key that is not already assigned to another attribute.

如果希望引入一个新属性，那么应当挑选一个还没有指定给其他属性的标识符键。

youdao