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关于php的uniqid生成唯一ID的疑问

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关于php的uniqid生成唯一ID的疑问

如下图，md5不是依赖输入么？为什么加md5就能绝对唯一了？求大神解答！

image.png


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by (71.8m points)

终于自己找到原因了，md5(uniqid(mt_rand(), true))，这个其实就是双随机+时间戳生成的唯一id，基本上，这个算法在很大程度上能保证唯一性了，但确实存在碰撞的可能。
image.png

结论：
1、md5(uniqid(mt_rand(), true)) 理论上确实存在碰撞可能
2、小公司放心用，大厂就谨慎使用


与恶龙缠斗过久,自身亦成为恶龙；凝视深渊过久,深渊将回以凝视…
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