hard-and-fast

基本解释

There is no hard-and-fast rule for the ratio because it depends on the queries involved.
对于这个比率，并没有什么严格的规则，因为这依赖于所涉及的查询。
There is no hard-and-fast rule for doing this, but adopting a proper link sequence for dependent shared libraries should work most of the time.
关于这一点，没有一成不变的规则，不过，为相关的共享库采用适当的链接顺序大部分时候都会管用。
Multiplayer online games accessed through a game console have hard-and-fast performance rules that derive from the fixed refresh rate of the display device.
通过游戏机访问的多玩家在线游戏具有严格且快速的性能规则，这是因为显示设备具有固定的刷新速率。

This is most certainly not a hard-and-fast rule, in general I've found it to be accurate.
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There are no hard-and-fast rules that determine if an IaaS cloud will provide savings to your business.
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Turner says it's very difficult to provide hard-and-fast earnings estimates for Northern Peru in these early days.
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If you say that there are no hard and fast rules, or that there is no hard and fast information about something, you are indicating that there are no fixed or definite rules or facts.