If you own the class, you can remove the constraint or else do something to enable an implicit reference or identity conversion.

如果您拥有类，则可移除约束或执行某一操作以启用隐式引用或标识转换。

youdao

For row change timestamp columns only, if the column is defined with the IMPLICITLY HIDDEN attribute, then it is not externalized when there is an implicit reference to the columns of the table.

对于行修改时间戳列(只针对这种列)，如果该列使用IMPLICITLY hidden属性定义，那么当对表列进行隐式引用时，不会对该列执行外部化。

youdao

Implicit class loading occurs when a class is loaded as result of a reference, instantiation, or inheritance (not via an explicit method call).

隐式类装入发生在由于引用、实例化或继承导致装入类的时候(不是通过显式方法调用)。

youdao