If you try to route from a map of France updated in May with a map of Germany updated in April, HH-Routing may not be compatible across the border. You would need to update all relevant maps to the same version.
At its core, a stream is just a sequence of data that arrives over time. You don't have all of it at once. You process it incrementally as it becomes available.
，这一点在爱思助手下载最新版本中也有详细论述
The blocks are linked together to create a history.
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