• Python 基于Python生成短8位唯一id解决方案


    基于Python生成短8位唯一id解决方案

    by:授客 QQ1033553122

    测试环境:

    Win10

    Python 3.5.4

     

    实现思路

    利用62个可打印字符,通过随机生成32位UUID,由于UUID都为十六进制,所以将UUID分成8组,每4个为一组,然后通过模62(字符0-9,a-z,A-Z总数量62个字符)操作,结果作为索引取出字符,这样重复率大大降低,实践测试,运行20000000次,仅出现2个重复id(仅测试过一次)。

     

    当然,这样还达不到唯一id,因为还是有重复的。解决方法呢,可以考虑结合数据库、或者其它存储来实现,以结合数据库为例,我们可以新建一张数据库表,并给表设置一个id字段,并且设置为主键、或者增加唯一约束,每次获取8 id后,往表里插入一条数据,如果可以成功插入,说明不重复,否则说明是重复id,再次尝试获取。

     

     

    核心代码

     

    #!/usr/bin/env python
    # -*- coding:utf-8 -*-
     
     
    '''
    @CreateTime: 2020/07/14 11:04
    @Author : shouke
    '''
     
     
    import uuid
    array = [ "0", "1", "2", "3", "4", "5","6", "7", "8", "9",
              "a", "b", "c", "d", "e", "f","g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s","t", "u", "v", "w", "x", "y", "z",
              "A", "B", "C", "D", "E", "F", "G", "H", "I","J", "K", "L", "M", "N", "O", "P", "Q", "R", "S", "T", "U", "V","W", "X", "Y", "Z"
              ]
     
    def get_short_id():
        id = str(uuid.uuid4()).replace("-", '') # 注意这里需要用uuid4
        buffer = []
        for i in range(0, 8):
            start = i *  4
            end = i * 4 + 4
            val = int(id[start:end], 16)
            buffer.append(array[val % 62])
        return "".join(buffer)
     

    测试验证

    id_set = set() # 用于存放生成的唯一id
    count = 0 # 用于统计出现重复的次数
    index = [] # 记录第几次调用生成8id出现重复
    for i in range(0, 20000000):
        id = get_short_id()
        if id in id_set:
            count += 1
            index.append(str(i+1))
        else:
            id_set.add(id)
        print('id%s, 运行第 %s , 重复数:%s , 重复率:%s, 出现重复次序 %s' % (id, i+1, count, count/(i+1)*100, ','.join(index)))

     

     

     

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  • 原文地址:https://www.cnblogs.com/shouke/p/13423073.html
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