如何生成尚未存储在数据库中的唯一数字(数百万条记录)

Is it possible to generate numbers that are 100% unique in a db with millions of records(+ growing)? How?

You could either make the numbers auto-incrementing so that every number is guaranteed to be unique, or you could create a random number, check to see if it exists, and if it does, create another random number, and then repeat this process until one doesn't exist.