我想产生一个精干的标识,应当作为不同系统/数据库的独特识别特征。 我阅读了这些例子,但我不理解,如何能够确保所生成的补贴在不同系统和数据库中是独特的。
我希望你能够帮助我在这里发言。
最佳做法
The idea behind a UUID is -- depending on how they are generated -- that there are so many values representable with 122-bits* that the chance of accidental collisions -- again, depending on how they are generated -- is very, very, very, very, very, very, very, very, small.
摘自Wikipedia的UUID第4版(Leach-Salz Random):
换言之,只是在今后100年内每二年生产10亿德国马克之后,仅仅制造一个重复的可能性约为50%。 如果地球上的每个人都拥有6亿万德国马克,则一个重复的可能性约为50%。
... however, these probabilities only hold when the UUIDs are generated using sufficient entropy.
当然,还有其他UUID的生成计划和“众所周知的GUIDs”,并非所有这些计划都适合“全球-unique”的使用。 (此外,由于插入的零散,未专门化的UUID倾向于不为初级/专门化钥匙工作:服务器NEWSE RequestNTID,以帮助处理这一问题。)
幸福 co。
页: 1 我不知道哪些用途是提高的,但我
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