请注意，如果函数、方法、触发器或视图中引用了某个全局变量，则不能删除该变量。

Please note that the global variable cannot be dropped if it is referenced in a function, method, trigger or view.

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在大多数情况下，编译器将捕捉对已删除的函数或变量的任何引用并发出警告。

In most cases, the compiler will catch any reference to the deleted function or variable and issue a warning.

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不论m - file是否被改变或删除，如果函数和永恒变量的断点被删除了，那么M - file中调试断点和初始化的断点变量都将被删除。

It removes debugging breakpoints in M-files and reinitializes persistent variables, since the breakpoints for a function and persistent variables are cleared whenever the M-file is changed or cleared.

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