您必须使用这种异常机制,除非客户机已经了解期望的数据项数量。
You must use this exception mechanism unless the client already knows how many data items to expect.
除非这项技术已经被证明,否则没有人会使用它。
Until the technology had been demonstrated, she said, no one would use it.
如果全局变量是在会话内创建,则其他会话不能使用它,除非已经提交了这个工作单元。
If a global variable is created within a session, then it cannot be used by other sessions until the unit of work has committed.
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