How can someone say that md5 is used to generate a unique id? Because the system time is used, the IDS generated by this function are not optimal. To generate an absolutely unique ID, use the md5 () function (please refer to the string function reference ). Someone recommends md5 (uniqid (rand (), true). how can someone say that md5 is used to generate a unique id?
Because the system time is used, the IDS generated by this function are not optimal. To generate an absolutely unique ID, use the md5 () function (please refer to the string function reference ).
Md5 (uniqid (rand (), true) is recommended.
If uniqid cannot be repeated, does md5 have no effect? Because md5 depends on input, it has nothing to do with whether it is unique or not.
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Your understanding is correct.
There is such a comment on the manual, which looks similar but has different meanings: (hmmm, this Chinese version of the manual is lagging behind, without this section)
This function does not generate cryptographically secure tokens, in fact without being passed any additional parameters the return value is little different from microtime (). if you need to generate cryptographically secure tokens use openssl_random_pseudo do_bytes ().
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